Systems and Methods for Fine Grain Policy Driven Cookie Proxying

ABSTRACT

The present solution enables a client that is not configured to use cookies to access resources of the server that uses cookies for communications with the clients. An intermediary deployed between a client and a server intercepts and modifies transmissions between the client and the server to compensate for the mismatch in configuration of the cookies between the client and the server. The present disclosure relates to a method for managing cookies by an intermediary for a client. An intermediary receives a response from a server to a request of a client. The response may comprise a uniform resource locator (URL) and a cookie. The intermediary may modify the response by removing the cookie from the response and inserting a unique client identifier into the URL. The intermediary may store the removed cookie in association with the unique client identifier and forward the modified response to the client.

RELATED APPLICATIONS

The present application claims priority to U.S. Provisional ApplicationNo. 61/023,849 filed on Jan. 26, 2008, incorporated herein by reference.

FIELD OF THE INVENTION

The present application generally relates to data communicationnetworks. In particular, the present application relates to systems andmethods for fine grain policy driven cookie proxying management,clientless cookie management and techniques for cookie proxying.

BACKGROUND OF THE INVENTION

An enterprise may provide various services across a network to a numberof different clients. Some of the clients may connect to the network viamore secured connections, while other clients may be using less securenetwork connections. Similarly, some of the clients may be configured touse cookies for network communication with servers, while other clientsmay not. In instances where cookies are used by a server of theenterprise to provide a service, a client that is not enabled to usecookies may have difficulty connecting and using the service. Suchvariations in network configurations and network connections among theclients may create challenges to the enterprise in providing services tothese clients.

BRIEF SUMMARY OF THE INVENTION

A solution is presented to enable the enterprise to offer the servicesto clients regardless of their cookie or cookie related securityconfigurations and in some embodiments, without sacrificing the securityand integrity of the transmissions. The solution presented enables aclient that is not configured to use cookies to access a server thatuses cookies for communication with the clients. An intermediarydeployed between a client and a server intercepts and modifiestransmissions between the client and the server to compensate for themismatch in configuration of the cookies between the client and theserver.

In some aspects, the present disclosure relates to a method for managingcookies by an intermediary for a client. An intermediary receives aresponse from a server to a request of a client. The response maycomprise a uniform resource locator (URL) and a cookie. The intermediarymay modify the response by removing the cookie from the response andinserting a unique client identifier into the URL. The intermediary maystore the removed cookie in association with the unique clientidentifier and forward the modified response to the client.

In some embodiments, a cookie manager matches one or more valuesassociated with the cookie comprised by the response to a cookie from aplurality of cookies. In further embodiments, the intermediary modifiesthe received response in response to the matching. In some embodiments,the intermediary receives the request from the client, the requestcomprising a request URL. The cookie manager may match the request URLwith the removed cookie from a plurality of cookies. In some embodimentsthe intermediary modifies the request URL by adding the removed cookieand forwards the modified request URL to the server. In furtherembodiments, the plurality of cookies are associated with at least oneof a domain name or at least one path provided by the request URL. Inyet further embodiments, the intermediary receives one or more namevalue pairs from the cookie manager in response to the matching. In someembodiments, the response comprises a plurality of cookies and themodified response comprises a plurality of client identifiers associatedwith the plurality of cookies. In other embodiments, the unique clientidentifier is a cookie proxy session cookie comprising a portion of thecookie.

In some embodiments, the intermediary receives the request from theclient, the request comprising a cookie proxy session cookie, the cookieproxy session cookie comprising a portion of the cookie. Theintermediary may match the cookie proxy session cookie to the cookie. Insome embodiments, the intermediary may modify the request by removingthe cookie proxy session cookie from the request and adding the cookieto the request and forward the request to the server.

In some aspects, an intermediary for managing cookies using a proxy on anetwork. A packet engine of an intermediary receives a response from aserver to a request of a client. The response may comprise a URL and acookie. A cookie proxy of the intermediary may modify the response byremoving the cookie from the response and insert a unique clientidentifier into the URL. A cookie manager of the intermediary may storethe removed cookie in association with the unique client identifier. Theintermediary may forward the modified response to the client.

In some embodiments, the response may further comprise one or morevalues associated with the cookie. The cookie manager may match one ormore values associated with the cookie to a cookie from a plurality ofcookies. In some embodiments, the intermediary modifies the receivedresponse in response to the matching. In some embodiments, the packetengine receives the request from the client. The request may comprise arequest URL and the cookie manager may match the request URL with theremoved cookie from a plurality of cookies. In some embodiments, theintermediary modifies the request URL by adding the removed cookie and

forwards the modified request URL to the server. In further embodiments,the plurality of cookies are associated with at least one of a domainname or at least one path provided by the request URL. In still furtherembodiments, the intermediary receives one or more name value pairs fromthe cookie manager in response to the matching. In some embodiments, theresponse comprises a plurality of cookies and the modified responsecomprises a plurality of client identifiers associated with theplurality of cookies. In some embodiments, the unique client identifieris a cookie proxy session cookie comprising a portion of the informationcomprised by the cookie.

In some embodiments, the intermediary receives the request from theclient. The request may comprise a cookie proxy session cookie. Thecookie proxy session cookie may comprise a portion of the cookie. Theintermediary may match the cookie proxy session cookie to the cookie andmodify the request of the client by removing the cookie proxy sessioncookie from the request and adding the cookie to the request. Theintermediary may forward the modified request to the server.

BRIEF DESCRIPTION OF THE FIGURES

The foregoing and other objects, aspects, features, and advantages ofthe invention will become more apparent and better understood byreferring to the following description taken in conjunction with theaccompanying drawings, in which:

FIGS. 1A, 1B and 1C are block diagrams of embodiments of a networkenvironment for a client to access a server via one or more appliances;

FIG. 1D is a block diagram of an embodiment of an environment fordelivering a computing environment from a server to a client via anappliance;

FIGS. 1E and 1F are block diagrams of embodiments of a computing device;

FIG. 2A is a block diagram of an embodiment of an intermediaryprocessing communications between a client and a server;

FIG. 2B is a block diagram of another embodiment of an intermediary foroptimizing, accelerating, load-balancing and routing communicationsbetween a client and a server;

FIG. 3A is a block diagram of an embodiment of a clientless virtualprivate network access to a server via the intermediary;

FIG. 3B is a block diagram of another embodiment of a clientless virtualprivate network access to a server via the intermediary;

FIG. 4A is a block diagram relating a number of embodiments of cookiemanagement;

FIG. 4B is a block diagram presenting a number of management sequencediagrams utilized in cookie management;

FIG. 4C is a block diagram presenting a number of embodiments of cookieproxy data flow, including the methods relating to cookie proxying; and

FIG. 5 is a flow diagram of an embodiment of a method for configurationdriven cookie proxying by an intermediary.

The features and advantages of the present invention will become moreapparent from the detailed description set forth below when taken inconjunction with the drawings, in which like reference charactersidentify corresponding elements throughout. In the drawings, likereference numbers generally indicate identical, functionally similar,and/or structurally similar elements.

DETAILED DESCRIPTION OF THE INVENTION A. Network and ComputingEnvironment

Prior to discussing the specifics of embodiments of the systems andmethods of an appliance and/or client, it may be helpful to discuss thenetwork and computing environments in which such embodiments may bedeployed. Referring now to FIG. 1A, an embodiment of a networkenvironment is depicted. In brief overview, the network environmentcomprises one or more clients 102 a-102 n (also generally referred to aslocal machine(s) 102, or client(s) 102) in communication with one ormore servers 106 a-106 n (also generally referred to as server(s) 106,or remote machine(s) 106) via one or more networks 104, 104′ (generallyreferred to as network 104). In some embodiments, a client 102communicates with a server 106 via an appliance 200.

Although FIG. 1A shows a network 104 and a network 104′ between theclients 102 and the servers 106, the clients 102 and the servers 106 maybe on the same network 104. The networks 104 and 104′ can be the sametype of network or different types of networks. The network 104 and/orthe network 104′ can be a local-area network (LAN), such as a companyIntranet, a metropolitan area network (MAN), or a wide area network(WAN), such as the Internet or the World Wide Web. In one embodiment,network 104′ may be a private network and network 104 may be a publicnetwork. In some embodiments, network 104 may be a private network andnetwork 104′ a public network. In another embodiment, networks 104 and104′ may both be private networks. In some embodiments, clients 102 maybe located at a branch office of a corporate enterprise communicatingvia a WAN connection over the network 104 to the servers 106 located ata corporate data center.

The network 104 and/or 104′ be any type and/or form of network and mayinclude any of the following: a point to point network, a broadcastnetwork, a wide area network, a local area network, a telecommunicationsnetwork, a data communication network, a computer network, an ATM(Asynchronous Transfer Mode) network, a SONET (Synchronous OpticalNetwork) network, a SDH (Synchronous Digital Hierarchy) network, awireless network and a wireline network. In some embodiments, thenetwork 104 may comprise a wireless link, such as an infrared channel orsatellite band. The topology of the network 104 and/or 104′ may be abus, star, or ring network topology. The network 104 and/or 104′ andnetwork topology may be of any such network or network topology as knownto those ordinarily skilled in the art capable of supporting theoperations described herein.

As shown in FIG. 1A, the appliance 200, which also may be referred to asan interface unit 200 or gateway 200, is shown between the networks 104and 104′. In some embodiments, the appliance 200 may be located onnetwork 104. For example, a branch office of a corporate enterprise maydeploy an appliance 200 at the branch office. In other embodiments, theappliance 200 may be located on network 104′. For example, an appliance200 may be located at a corporate data center. In yet anotherembodiment, a plurality of appliances 200 may be deployed on network104. In some embodiments, a plurality of appliances 200 may be deployedon network 104′. In one embodiment, a first appliance 200 communicateswith a second appliance 200′. In other embodiments, the appliance 200could be a part of any client 102 or server 106 on the same or differentnetwork 104,104′ as the client 102. One or more appliances 200 may belocated at any point in the network or network communications pathbetween a client 102 and a server 106.

In some embodiments, the appliance 200 comprises any of the networkdevices manufactured by Citrix Systems, Inc. of Ft. Lauderdale Fla.,referred to as Citrix NetScaler devices. In other embodiments, theappliance 200 includes any of the product embodiments referred to asWebAccelerator and BigIP manufactured by F5 Networks, Inc. of Seattle,Wash. In another embodiment, the appliance 205 includes any of the DXacceleration device platforms and/or the SSL VPN series of devices, suchas SA 700, SA 2000, SA 4000, and SA 6000 devices manufactured by JuniperNetworks, Inc. of Sunnyvale, Calif. In yet another embodiment, theappliance 200 includes any application acceleration and/or securityrelated appliances and/or software manufactured by Cisco Systems, Inc.of San Jose, Calif., such as the Cisco ACE Application Control EngineModule service software and network modules, and Cisco AVS SeriesApplication Velocity System.

In one embodiment, the system may include multiple, logically-groupedservers 106. In these embodiments, the logical group of servers may bereferred to as a server farm 38. In some of these embodiments, theserves 106 may be geographically dispersed. In some cases, a farm 38 maybe administered as a single entity. In other embodiments, the serverfarm 38 comprises a plurality of server farms 38. In one embodiment, theserver farm executes one or more applications on behalf of one or moreclients 102.

The servers 106 within each farm 38 can be heterogeneous. One or more ofthe servers 106 can operate according to one type of operating systemplatform (e.g., WINDOWS NT, manufactured by Microsoft Corp. of Redmond,Wash.), while one or more of the other servers 106 can operate onaccording to another type of operating system platform (e.g., Unix orLinux). The servers 106 of each farm 38 do not need to be physicallyproximate to another server 106 in the same farm 38. Thus, the group ofservers 106 logically grouped as a farm 38 may be interconnected using awide-area network (WAN) connection or medium-area network (MAN)connection. For example, a farm 38 may include servers 106 physicallylocated in different continents or different regions of a continent,country, state, city, campus, or room. Data transmission speeds betweenservers 106 in the farm 38 can be increased if the servers 106 areconnected using a local-area network (LAN) connection or some form ofdirect connection.

Servers 106 may be referred to as a file server, application server, webserver, proxy server, or gateway server. In some embodiments, a server106 may have the capacity to function as either an application server oras a master application server. In one embodiment, a server 106 mayinclude an Active Directory. The clients 102 may also be referred to asclient nodes or endpoints. In some embodiments, a client 102 has thecapacity to function as both a client node seeking access toapplications on a server and as an application server providing accessto hosted applications for other clients 102 a-102 n.

In some embodiments, a client 102 communicates with a server 106. In oneembodiment, the client 102 communicates directly with one of the servers106 in a farm 38. In another embodiment, the client 102 executes aprogram neighborhood application to communicate with a server 106 in afarm 38. In still another embodiment, the server 106 provides thefunctionality of a master node. In some embodiments, the client 102communicates with the server 106 in the farm 38 through a network 104.Over the network 104, the client 102 can, for example, request executionof various applications hosted by the servers 106 a-106 n in the farm 38and receive output of the results of the application execution fordisplay. In some embodiments, only the master node provides thefunctionality required to identify and provide address informationassociated with a server 106′ hosting a requested application.

In one embodiment, the server 106 provides functionality of a webserver. In another embodiment, the server 106 a receives requests fromthe client 102, forwards the requests to a second server 106 b andresponds to the request by the client 102 with a response to the requestfrom the server 106 b. In still another embodiment, the server 106acquires an enumeration of applications available to the client 102 andaddress information associated with a server 106 hosting an applicationidentified by the enumeration of applications. In yet anotherembodiment, the server 106 presents the response to the request to theclient 102 using a web interface. In one embodiment, the client 102communicates directly with the server 106 to access the identifiedapplication. In another embodiment, the client 102 receives applicationoutput data, such as display data, generated by an execution of theidentified application on the server 106.

Referring now to FIG. 1B, an embodiment of a network environmentdeploying multiple appliances 200 is depicted. A first appliance 200 maybe deployed on a first network 104 and a second appliance 200′ on asecond network 104′. For example a corporate enterprise may deploy afirst appliance 200 at a branch office and a second appliance 200′ at adata center. In another embodiment, the first appliance 200 and secondappliance 200′ are deployed on the same network 104 or network 104. Forexample, a first appliance 200 may be deployed for a first server farm38, and a second appliance 200 may be deployed for a second server farm38′. In another example, a first appliance 200 may be deployed at afirst branch office while the second appliance 200′ is deployed at asecond branch office′. In some embodiments, the first appliance 200 andsecond appliance 200′ work in cooperation or in conjunction with eachother to accelerate network traffic or the delivery of application anddata between a client and a server

Referring now to FIG. 1C, another embodiment of a network environmentdeploying the appliance 200 with one or more other types of appliances,such as between one or more WAN optimization appliance 205, 205′ isdepicted. For example a first WAN optimization appliance 205 is shownbetween networks 104 and 104′ and s second WAN optimization appliance205′ may be deployed between the appliance 200 and one or more servers106. By way of example, a corporate enterprise may deploy a first WANoptimization appliance 205 at a branch office and a second WANoptimization appliance 205′ at a data center. In some embodiments, theappliance 205 may be located on network 104′. In other embodiments, theappliance 205′ may be located on network 104. In some embodiments, theappliance 205′ may be located on network 104′ or network 104″. In oneembodiment, the appliance 205 and 205′ are on the same network. Inanother embodiment, the appliance 205 and 205′ are on differentnetworks. In another example, a first WAN optimization appliance 205 maybe deployed for a first server farm 38 and a second WAN optimizationappliance 205′ for a second server farm 38′

In one embodiment, the appliance 205 is a device for accelerating,optimizing or otherwise improving the performance, operation, or qualityof service of any type and form of network traffic, such as traffic toand/or from a WAN connection. In some embodiments, the appliance 205 isa performance enhancing proxy. In other embodiments, the appliance 205is any type and form of WAN optimization or acceleration device,sometimes also referred to as a WAN optimization controller. In oneembodiment, the appliance 205 is any of the product embodiments referredto as WANScaler manufactured by Citrix Systems, Inc. of Ft. Lauderdale,Fla. In other embodiments, the appliance 205 includes any of the productembodiments referred to as BIG-IP link controller and WANjetmanufactured by F5 Networks, Inc. of Seattle, Wash. In anotherembodiment, the appliance 205 includes any of the WX and WXC WANacceleration device platforms manufactured by Juniper Networks, Inc. ofSunnyvale, Calif. In some embodiments, the appliance 205 includes any ofthe steelhead line of WAN optimization appliances manufactured byRiverbed Technology of San Francisco, Calif. In other embodiments, theappliance 205 includes any of the WAN related devices manufactured byExpand Networks Inc. of Roseland, New Jersey. In one embodiment, theappliance 205 includes any of the WAN related appliances manufactured byPacketeer Inc. of Cupertino, California, such as the PacketShaper,iShared, and SkyX product embodiments provided by Packeteer. In yetanother embodiment, the appliance 205 includes any WAN relatedappliances and/or software manufactured by Cisco Systems, Inc. of SanJose, Calif., such as the Cisco Wide Area Network Application Servicessoftware and network modules, and Wide Area Network engine appliances.

In one embodiment, the appliance 205 provides application and dataacceleration services for branch-office or remote offices. In oneembodiment, the appliance 205 includes optimization of Wide Area FileServices (WAFS). In another embodiment, the appliance 205 acceleratesthe delivery of files, such as via the Common Internet File System(CIFS) protocol. In other embodiments, the appliance 205 providescaching in memory and/or storage to accelerate delivery of applicationsand data. In one embodiment, the appliance 205 provides compression ofnetwork traffic at any level of the network stack or at any protocol ornetwork layer. In another embodiment, the appliance 205 providestransport layer protocol optimizations, flow control, performanceenhancements or modifications and/or management to accelerate deliveryof applications and data over a WAN connection. For example, in oneembodiment, the appliance 205 provides Transport Control Protocol (TCP)optimizations. In other embodiments, the appliance 205 providesoptimizations, flow control, performance enhancements or modificationsand/or management for any session or application layer protocol.

In another embodiment, the appliance 205 encoded any type and form ofdata or information into custom or standard TCP and/or IP header fieldsor option fields of network packet to announce presence, functionalityor capability to another appliance 205′. In another embodiment, anappliance 205′ may communicate with another appliance 205′ using dataencoded in both TCP and/or IP header fields or options. For example, theappliance may use TCP option(s) or IP header fields or options tocommunicate one or more parameters to be used by the appliances 205,205′ in performing functionality, such as WAN acceleration, or forworking in conjunction with each other.

In some embodiments, the appliance 200 preserves any of the informationencoded in TCP and/or IP header and/or option fields communicatedbetween appliances 205 and 205′. For example, the appliance 200 mayterminate a transport layer connection traversing the appliance 200,such as a transport layer connection from between a client and a servertraversing appliances 205 and 205′. In one embodiment, the appliance 200identifies and preserves any encoded information in a transport layerpacket transmitted by a first appliance 205 via a first transport layerconnection and communicates a transport layer packet with the encodedinformation to a second appliance 205′ via a second transport layerconnection.

Referring now to FIG. 1D, a network environment for delivering and/oroperating a computing environment on a client 102 is depicted. In someembodiments, a server 106 includes an application delivery system 190for delivering a computing environment or an application and/or datafile to one or more clients 102. In brief overview, a client 10 is incommunication with a server 106 via network 104, 104′ and appliance 200.For example, the client 102 may reside in a remote office of a company,e.g., a branch office, and the server 106 may reside at a corporate datacenter. The client 102 comprises a client agent 120, and a computingenvironment 15. The computing environment 15 may execute or operate anapplication that accesses, processes or uses a data file. The computingenvironment 15, application and/or data file may be delivered via theappliance 200 and/or the server 106.

In some embodiments, the appliance 200 accelerates delivery of acomputing environment 15, or any portion thereof, to a client 102. Inone embodiment, the appliance 200 accelerates the delivery of thecomputing environment 15 by the application delivery system 190. Forexample, the embodiments described herein may be used to acceleratedelivery of a streaming application and data file processable by theapplication from a central corporate data center to a remote userlocation, such as a branch office of the company. In another embodiment,the appliance 200 accelerates transport layer traffic between a client102 and a server 106. The appliance 200 may provide accelerationtechniques for accelerating any transport layer payload from a server106 to a client 102, such as: 1) transport layer connection pooling, 2)transport layer connection multiplexing, 3) transport control protocolbuffering, 4) compression and 5) caching. In some embodiments, theappliance 200 provides load balancing of servers 106 in responding torequests from clients 102. In other embodiments, the appliance 200 actsas a proxy or access server to provide access to the one or more servers106. In another embodiment, the appliance 200 provides a secure virtualprivate network connection from a first network 104 of the client 102 tothe second network 104′ of the server 106, such as an SSL VPNconnection. It yet other embodiments, the appliance 200 providesapplication firewall security, control and management of the connectionand communications between a client 102 and a server 106.

In some embodiments, the application delivery management system 190provides application delivery techniques to deliver a computingenvironment to a desktop of a user, remote or otherwise, based on aplurality of execution methods and based on any authentication andauthorization policies applied via a policy engine 195. With thesetechniques, a remote user may obtain a computing environment and accessto server stored applications and data files from any network connecteddevice 100. In one embodiment, the application delivery system 190 mayreside or execute on a server 106. In another embodiment, theapplication delivery system 190 may reside or execute on a plurality ofservers 106 a-106 n. In some embodiments, the application deliverysystem 190 may execute in a server farm 38. In one embodiment, theserver 106 executing the application delivery system 190 may also storeor provide the application and data file. In another embodiment, a firstset of one or more servers 106 may execute the application deliverysystem 190, and a different server 106 n may store or provide theapplication and data file. In some embodiments, each of the applicationdelivery system 190, the application, and data file may reside or belocated on different servers. In yet another embodiment, any portion ofthe application delivery system 190 may reside, execute or be stored onor distributed to the appliance 200, or a plurality of appliances.

The client 102 may include a computing environment 15 for executing anapplication that uses or processes a data file. The client 102 vianetworks 104, 104′ and appliance 200 may request an application and datafile from the server 106. In one embodiment, the appliance 200 mayforward a request from the client 102 to the server 106. For example,the client 102 may not have the application and data file stored oraccessible locally. In response to the request, the application deliverysystem 190 and/or server 106 may deliver the application and data fileto the client 102. For example, in one embodiment, the server 106 maytransmit the application as an application stream to operate incomputing environment 15 on client 102.

In some embodiments, the application delivery system 190 comprises anyportion of the Citrix Access Suite™ by Citrix Systems, Inc., such as theMetaFrame or Citrix Presentation Server™ and/or any of the Microsoft®Windows Terminal Services manufactured by the Microsoft Corporation. Inone embodiment, the application delivery system 190 may deliver one ormore applications to clients 102 or users via a remote-display protocolor otherwise via remote-based or server-based computing. In anotherembodiment, the application delivery system 190 may deliver one or moreapplications to clients or users via steaming of the application.

In one embodiment, the application delivery system 190 includes a policyengine 195 for controlling and managing the access to, selection ofapplication execution methods and the delivery of applications. In someembodiments, the policy engine 195 determines the one or moreapplications a user or client 102 may access. In another embodiment, thepolicy engine 195 determines how the application should be delivered tothe user or client 102, e.g., the method of execution. In someembodiments, the application delivery system 190 provides a plurality ofdelivery techniques from which to select a method of applicationexecution, such as a server-based computing, streaming or delivering theapplication locally to the client 120 for local execution.

In one embodiment, a client 102 requests execution of an applicationprogram and the application delivery system 190 comprising a server 106selects a method of executing the application program. In someembodiments, the server 106 receives credentials from the client 102. Inanother embodiment, the server 106 receives a request for an enumerationof available applications from the client 102. In one embodiment, inresponse to the request or receipt of credentials, the applicationdelivery system 190 enumerates a plurality of application programsavailable to the client 102. The application delivery system 190receives a request to execute an enumerated application. The applicationdelivery system 190 selects one of a predetermined number of methods forexecuting the enumerated application, for example, responsive to apolicy of a policy engine. The application delivery system 190 mayselect a method of execution of the application enabling the client 102to receive application-output data generated by execution of theapplication program on a server 106. The application delivery system 190may select a method of execution of the application enabling the localmachine 10 to execute the application program locally after retrieving aplurality of application files comprising the application. In yetanother embodiment, the application delivery system 190 may select amethod of execution of the application to stream the application via thenetwork 104 to the client 102.

A client 102 may execute, operate or otherwise provide an application,which can be any type and/or form of software, program, or executableinstructions such as any type and/or form of web browser, web-basedclient, client-server application, a thin-client computing client, anActiveX control, or a Java applet, or any other type and/or form ofexecutable instructions capable of executing on client 102. In someembodiments, the application may be a server-based or a remote-basedapplication executed on behalf of the client 102 on a server 106. In oneembodiments the server 106 may display output to the client 102 usingany thin-client or remote-display protocol, such as the IndependentComputing Architecture (ICA) protocol manufactured by Citrix Systems,Inc. of Ft. Lauderdale, Fla. or the Remote Desktop Protocol (RDP)manufactured by the Microsoft Corporation of Redmond, Wash. Theapplication can use any type of protocol and it can be, for example, anHTTP client, an FTP client, an Oscar client, or a Telnet client. Inother embodiments, the application comprises any type of softwarerelated to VoIP communications, such as a soft IP telephone. In furtherembodiments, the application comprises any application related toreal-time data communications, such as applications for streaming videoand/or audio.

In some embodiments, the server 106 or a server farm 38 may be runningone or more applications, such as an application providing a thin-clientcomputing or remote display presentation application. In one embodiment,the server 106 or server farm 38 executes as an application, any portionof the Citrix Access Suite™ by Citrix Systems, Inc., such as theMetaFrame or Citrix Presentation Server™, and/or any of the Microsoft®Windows Terminal Services manufactured by the Microsoft Corporation. Inone embodiment, the application is an ICA client, developed by CitrixSystems, Inc. of Fort Lauderdale, Fla. In other embodiments, theapplication includes a Remote Desktop (RDP) client, developed byMicrosoft Corporation of Redmond, Wash. Also, the server 106 may run anapplication, which for example, may be an application server providingemail services such as Microsoft Exchange manufactured by the MicrosoftCorporation of Redmond, Wash., a web or Internet server, or a desktopsharing server, or a collaboration server. In some embodiments, any ofthe applications may comprise any type of hosted service or products,such as GoToMeeting™ provided by Citrix Online Division, Inc. of SantaBarbara, Calif., WebEx™ provided by WebEx, Inc. of Santa Clara, Calif.,or Microsoft Office Live Meeting provided by Microsoft Corporation ofRedmond, Wash.

Still referring to FIG. 1D, an embodiment of the network environment mayinclude a monitoring server 106A. The monitoring server 106A may includeany type and form performance monitoring service 198. The performancemonitoring service 198 may include monitoring, measurement and/ormanagement software and/or hardware, including data collection,aggregation, analysis, management and reporting. In one embodiment, theperformance monitoring service 198 includes one or more monitoringagents 197. The monitoring agent 197 includes any software, hardware orcombination thereof for performing monitoring, measurement and datacollection activities on a device, such as a client 102, server 106 oran appliance 200, 205. In some embodiments, the monitoring agent 197includes any type and form of script, such as Visual Basic script, orJavascript. In one embodiment, the monitoring agent 197 executestransparently to any application and/or user of the device. In someembodiments, the monitoring agent 197 is installed and operatedunobtrusively to the application or client. In yet another embodiment,the monitoring agent 197 is installed and operated without anyinstrumentation for the application or device.

In some embodiments, the monitoring agent 197 monitors, measures andcollects data on a predetermined frequency. In other embodiments, themonitoring agent 197 monitors, measures and collects data based upondetection of any type and form of event. For example, the monitoringagent 197 may collect data upon detection of a request for a web page orreceipt of an HTTP response. In another example, the monitoring agent197 may collect data upon detection of any user input events, such as amouse click. The monitoring agent 197 may report or provide anymonitored, measured or collected data to the monitoring service 198. Inone embodiment, the monitoring agent 197 transmits information to themonitoring service 198 according to a schedule or a predeterminedfrequency. In another embodiment, the monitoring agent 197 transmitsinformation to the monitoring service 198 upon detection of an event.

In some embodiments, the monitoring service 198 and/or monitoring agent197 performs monitoring and performance measurement of any networkresource or network infrastructure element, such as a client, server,server farm, appliance 200, appliance 205, or network connection. In oneembodiment, the monitoring service 198 and/or monitoring agent 197performs monitoring and performance measurement of any transport layerconnection, such as a TCP or UDP connection. In another embodiment, themonitoring service 198 and/or monitoring agent 197 monitors and measuresnetwork latency. In yet one embodiment, the monitoring service 198and/or monitoring agent 197 monitors and measures bandwidth utilization.

In other embodiments, the monitoring service 198 and/or monitoring agent197 monitors and measures end-user response times. In some embodiments,the monitoring service 198 performs monitoring and performancemeasurement of an application. In another embodiment, the monitoringservice 198 and/or monitoring agent 197 performs monitoring andperformance measurement of any session or connection to the application.In one embodiment, the monitoring service 198 and/or monitoring agent197 monitors and measures performance of a browser. In anotherembodiment, the monitoring service 198 and/or monitoring agent 197monitors and measures performance of HTTP based transactions. In someembodiments, the monitoring service 198 and/or monitoring agent 197monitors and measures performance of a Voice over IP (VoIP) applicationor session. In other embodiments, the monitoring service 198 and/ormonitoring agent 197 monitors and measures performance of a remotedisplay protocol application, such as an ICA client or RDP client. Inyet another embodiment, the monitoring service 198 and/or monitoringagent 197 monitors and measures performance of any type and form ofstreaming media. In still a further embodiment, the monitoring service198 and/or monitoring agent 197 monitors and measures performance of ahosted application or a Software-As-A-Service (SaaS) delivery model.

In some embodiments, the monitoring service 198 and/or monitoring agent197 performs monitoring and performance measurement of one or moretransactions, requests or responses related to application. In otherembodiments, the monitoring service 198 and/or monitoring agent 197monitors and measures any portion of an application layer stack, such asany .NET or J2EE calls. In one embodiment, the monitoring service 198and/or monitoring agent 197 monitors and measures database or SQLtransactions. In yet another embodiment, the monitoring service 198and/or monitoring agent 197 monitors and measures any method, functionor application programming interface (API) call.

In one embodiment, the monitoring service 198 and/or monitoring agent197 performs monitoring and performance measurement of a delivery ofapplication and/or data from a server to a client via one or moreappliances, such as appliance 200 and/or appliance 205. In someembodiments, the monitoring service 198 and/or monitoring agent 197monitors and measures performance of delivery of a virtualizedapplication. In other embodiments, the monitoring service 198 and/ormonitoring agent 197 monitors and measures performance of delivery of astreaming application. In another embodiment, the monitoring service 198and/or monitoring agent 197 monitors and measures performance ofdelivery of a desktop application to a client and/or the execution ofthe desktop application on the client. In another embodiment, themonitoring service 198 and/or monitoring agent 197 monitors and measuresperformance of a client/server application.

In one embodiment, the monitoring service 198 and/or monitoring agent197 is designed and constructed to provide application performancemanagement for the application delivery system 190. For example, themonitoring service 198 and/or monitoring agent 197 may monitor, measureand manage the performance of the delivery of applications via theCitrix Presentation Server. In this example, the monitoring service 198and/or monitoring agent 197 monitors individual ICA sessions. Themonitoring service 198 and/or monitoring agent 197 may measure the totaland per session system resource usage, as well as application andnetworking performance. The monitoring service 198 and/or monitoringagent 197 may identify the active servers for a given user and/or usersession. In some embodiments, the monitoring service 198 and/ormonitoring agent 197 monitors back-end connections between theapplication delivery system 190 and an application and/or databaseserver. The monitoring service 198 and/or monitoring agent 197 maymeasure network latency, delay and volume per user-session or ICAsession.

In some embodiments, the monitoring service 198 and/or monitoring agent197 measures and monitors memory usage for the application deliverysystem 190, such as total memory usage, per user session and/or perprocess. In other embodiments, the monitoring service 198 and/ormonitoring agent 197 measures and monitors CPU usage the applicationdelivery system 190, such as total CPU usage, per user session and/orper process. In another embodiments, the monitoring service 198 and/ormonitoring agent 197 measures and monitors the time required to log-into an application, a server, or the application delivery system, such asCitrix Presentation Server. In one embodiment, the monitoring service198 and/or monitoring agent 197 measures and monitors the duration auser is logged into an application, a server, or the applicationdelivery system 190. In some embodiments, the monitoring service 198and/or monitoring agent 197 measures and monitors active and inactivesession counts for an application, server or application delivery systemsession. In yet another embodiment, the monitoring service 198 and/ormonitoring agent 197 measures and monitors user session latency.

In yet further embodiments, the monitoring service 198 and/or monitoringagent 197 measures and monitors measures and monitors any type and formof server metrics. In one embodiment, the monitoring service 198 and/ormonitoring agent 197 measures and monitors metrics related to systemmemory, CPU usage, and disk storage. In another embodiment, themonitoring service 198 and/or monitoring agent 197 measures and monitorsmetrics related to page faults, such as page faults per second. In otherembodiments, the monitoring service 198 and/or monitoring agent 197measures and monitors round-trip time metrics. In yet anotherembodiment, the monitoring service 198 and/or monitoring agent 197measures and monitors metrics related to application crashes, errorsand/or hangs.

In some embodiments, the monitoring service 198 and monitoring agent 198includes any of the product embodiments referred to as EdgeSightmanufactured by Citrix Systems, Inc. of Ft. Lauderdale, Fla. In anotherembodiment, the performance monitoring service 198 and/or monitoringagent 198 includes any portion of the product embodiments referred to asthe TrueView product suite manufactured by the Symphoniq Corporation ofPalo Alto, Calif. In one embodiment, the performance monitoring service198 and/or monitoring agent 198 includes any portion of the productembodiments referred to as the TeaLeaf CX product suite manufactured bythe TeaLeaf Technology Inc. of San Francisco, Calif. In otherembodiments, the performance monitoring service 198 and/or monitoringagent 198 includes any portion of the business service managementproducts, such as the BMC Performance Manager and Patrol products,manufactured by BMC Software, Inc. of Houston, Tex.

The client 102, server 106, and appliance 200 may be deployed as and/orexecuted on any type and form of computing device, such as a computer,network device or appliance capable of communicating on any type andform of network and performing the operations described herein. FIGS. 1Eand 1F depict block diagrams of a computing device 100 useful forpracticing an embodiment of the client 102, server 106 or appliance 200.As shown in FIGS. 1E and 1F, each computing device 100 includes acentral processing unit 101, and a main memory unit 122. As shown inFIG. 1E, a computing device 100 may include a visual display device 124,a keyboard 126 and/or a pointing device 127, such as a mouse. Eachcomputing device 100 may also include additional optional elements, suchas one or more input/output devices 130 a-130 b (generally referred tousing reference numeral 130), and a cache memory 140 in communicationwith the central processing unit 101.

The central processing unit 101 is any logic circuitry that responds toand processes instructions fetched from the main memory unit 122. Inmany embodiments, the central processing unit is provided by amicroprocessor unit, such as: those manufactured by Intel Corporation ofMountain View, Calif.; those manufactured by Motorola Corporation ofSchaumburg, Illinois; those manufactured by Transmeta Corporation ofSanta Clara, Calif.; the RS/6000 processor, those manufactured byInternational Business Machines of White Plains, New York; or thosemanufactured by Advanced Micro Devices of Sunnyvale, Calif. Thecomputing device 100 may be based on any of these processors, or anyother processor capable of operating as described herein.

Main memory unit 122 may be one or more memory chips capable of storingdata and allowing any storage location to be directly accessed by themicroprocessor 101, such as Static random access memory (SRAM), BurstSRAM or SynchBurst SRAM (BSRAM), Dynamic random access memory (DRAM),Fast Page Mode DRAM (FPM DRAM), Enhanced DRAM (EDRAM), Extended DataOutput RAM (EDO RAM), Extended Data Output DRAM (EDO DRAM), BurstExtended Data Output DRAM (BEDO DRAM), Enhanced DRAM (EDRAM),synchronous DRAM (SDRAM), JEDEC SRAM, PC100 SDRAM, Double Data RateSDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), SyncLink DRAM (SLDRAM),Direct Rambus DRAM (DRDRAM), or Ferroelectric RAM (FRAM). The mainmemory 122 may be based on any of the above described memory chips, orany other available memory chips capable of operating as describedherein. In the embodiment shown in FIG. 1E, the processor 101communicates with main memory 122 via a system bus 150 (described inmore detail below). FIG. 1E depicts an embodiment of a computing device100 in which the processor communicates directly with main memory 122via a memory port 103. For example, in FIG. 1F the main memory 122 maybe DRDRAM.

FIG. 1F depicts an embodiment in which the main processor 101communicates directly with cache memory 140 via a secondary bus,sometimes referred to as a backside bus. In other embodiments, the mainprocessor 101 communicates with cache memory 140 using the system bus150. Cache memory 140 typically has a faster response time than mainmemory 122 and is typically provided by SRAM, BSRAM, or EDRAM. In theembodiment shown in FIG. 1E, the processor 101 communicates with variousI/O devices 130 via a local system bus 150. Various busses may be usedto connect the central processing unit 101 to any of the I/O devices130, including a VESA VL bus, an ISA bus, an EISA bus, a MicroChannelArchitecture (MCA) bus, a PCI bus, a PCI-X bus, a PCI-Express bus, or aNuBus. For embodiments in which the I/O device is a video display 124,the processor 101 may use an Advanced Graphics Port (AGP) to communicatewith the display 124. FIG. 1F depicts an embodiment of a computer 100 inwhich the main processor 101 communicates directly with I/O device 130via HyperTransport, Rapid I/O, or InfiniBand. FIG. 1F also depicts anembodiment in which local busses and direct communication are mixed: theprocessor 101 communicates with I/O device 130 using a localinterconnect bus while communicating with I/O device 130 directly.

The computing device 100 may support any suitable installation device116, such as a floppy disk drive for receiving floppy disks such as3.5-inch, 5.25-inch disks or ZIP disks, a CD-ROM drive, a CD-R/RW drive,a DVD-ROM drive, tape drives of various formats, USB device, hard-driveor any other device suitable for installing software and programs suchas any client agent 120, or portion thereof. The computing device 100may further comprise a storage device 128, such as one or more hard diskdrives or redundant arrays of independent disks, for storing anoperating system and other related software, and for storing applicationsoftware programs such as any program related to the client agent 120.Optionally, any of the installation devices 116 could also be used asthe storage device 128. Additionally, the operating system and thesoftware can be run from a bootable medium, for example, a bootable CD,such as KNOPPIX®, a bootable CD for GNU/Linux that is available as aGNU/Linux distribution from knoppix.net.

Furthermore, the computing device 100 may include a network interface118 to interface to a Local Area Network (LAN), Wide Area Network (WAN)or the Internet through a variety of connections including, but notlimited to, standard telephone lines, LAN or WAN links (e.g., 802.11,T1, T3, 56 kb, X.25), broadband connections (e.g., ISDN, Frame Relay,ATM), wireless connections, or some combination of any or all of theabove. The network interface 118 may comprise a built-in networkadapter, network interface card, PCMCIA network card, card bus networkadapter, wireless network adapter, USB network adapter, modem or anyother device suitable for interfacing the computing device 100 to anytype of network capable of communication and performing the operationsdescribed herein. A wide variety of I/O devices 130 a-130 n may bepresent in the computing device 100. Input devices include keyboards,mice, trackpads, trackballs, microphones, and drawing tablets. Outputdevices include video displays, speakers, inkjet printers, laserprinters, and dye-sublimation printers. The I/O devices 130 may becontrolled by an I/O controller 123 as shown in FIG. 1E. The I/Ocontroller may control one or more I/O devices such as a keyboard 126and a pointing device 127, e.g., a mouse or optical pen. Furthermore, anI/O device may also provide storage 128 and/or an installation medium116 for the computing device 100. In still other embodiments, thecomputing device 100 may provide USB connections to receive handheld USBstorage devices such as the USB Flash Drive line of devices manufacturedby Twintech Industry, Inc. of Los Alamitos, California.

In some embodiments, the computing device 100 may comprise or beconnected to multiple display devices 124 a-124 n, which each may be ofthe same or different type and/or form. As such, any of the I/O devices130 a-130 n and/or the I/O controller 123 may comprise any type and/orform of suitable hardware, software, or combination of hardware andsoftware to support, enable or provide for the connection and use ofmultiple display devices 124 a-124 n by the computing device 100. Forexample, the computing device 100 may include any type and/or form ofvideo adapter, video card, driver, and/or library to interface,communicate, connect or otherwise use the display devices 124 a-124 n.In one embodiment, a video adapter may comprise multiple connectors tointerface to multiple display devices 124 a-124 n. In other embodiments,the computing device 100 may include multiple video adapters, with eachvideo adapter connected to one or more of the display devices 124 a-124n. In some embodiments, any portion of the operating system of thecomputing device 100 may be configured for using multiple displays 124a-124 n. In other embodiments, one or more of the display devices 124a-124 n may be provided by one or more other computing devices, such ascomputing devices 100 a and 100 b connected to the computing device 100,for example, via a network. These embodiments may include any type ofsoftware designed and constructed to use another computer's displaydevice as a second display device 124 a for the computing device 100.One ordinarily skilled in the art will recognize and appreciate thevarious ways and embodiments that a computing device 100 may beconfigured to have multiple display devices 124 a-124 n.

In further embodiments, an I/O device 130 may be a bridge 170 betweenthe system bus 150 and an external communication bus, such as a USB bus,an Apple Desktop Bus, an RS-232 serial connection, a SCSI bus, aFireWire bus, a FireWire 800 bus, an Ethernet bus, an AppleTalk bus, aGigabit Ethernet bus, an Asynchronous Transfer Mode bus, a HIPPI bus, aSuper HIPPI bus, a SerialPlus bus, a SCI/LAMP bus, a FibreChannel bus,or a Serial Attached small computer system interface bus.

A computing device 100 of the sort depicted in FIGS. 1E and 1F typicallyoperate under the control of operating systems, which control schedulingof tasks and access to system resources. The computing device 100 can berunning any operating system such as any of the versions of theMicrosoft® Windows operating systems, the different releases of the Unixand Linux operating systems, any version of the Mac OS® for Macintoshcomputers, any embedded operating system, any real-time operatingsystem, any open source operating system, any proprietary operatingsystem, any operating systems for mobile computing devices, or any otheroperating system capable of running on the computing device andperforming the operations described herein. Typical operating systemsinclude: WINDOWS 3.x, WINDOWS 95, WINDOWS 98, WINDOWS 2000, WINDOWS NT3.51, WINDOWS NT 4.0, WINDOWS CE, and WINDOWS XP, all of which aremanufactured by Microsoft Corporation of Redmond, Wash.; MacOS,manufactured by Apple Computer of Cupertino, California; OS/2,manufactured by International Business Machines of Armonk, N.Y.; andLinux, a freely-available operating system distributed by Caldera Corp.of Salt Lake City, Utah, or any type and/or form of a Unix operatingsystem, among others.

In other embodiments, the computing device 100 may have differentprocessors, operating systems, and input devices consistent with thedevice. For example, in one embodiment the computer 100 is a Treo 180,270, 1060, 600 or 650 smart phone manufactured by Palm, Inc. In thisembodiment, the Treo smart phone is operated under the control of thePalmOS operating system and includes a stylus input device as well as afive-way navigator device. Moreover, the computing device 100 can be anyworkstation, desktop computer, laptop or notebook computer, server,handheld computer, mobile telephone, any other computer, or other formof computing or telecommunications device that is capable ofcommunication and that has sufficient processor power and memorycapacity to perform the operations described herein.

B. Appliance Architecture

FIG. 2A illustrates an example embodiment of the appliance 200, whichmay also be referred to as the intermediary 200, Proxy or Netscaler. Thearchitecture of the appliance 200 in FIG. 2A is provided by way ofillustration only and is not intended to be limiting. As shown in FIG.2, appliance 200 comprises a hardware layer 206 and a software layerdivided into a user space 202 and a kernel space 204.

Hardware layer 206 provides the hardware elements upon which programsand services within kernel space 204 and user space 202 are executed.Hardware layer 206 also provides the structures and elements which allowprograms and services within kernel space 204 and user space 202 tocommunicate data both internally and externally with respect toappliance 200. As shown in FIG. 2, the hardware layer 206 includes aprocessing unit 262 for executing software programs and services, amemory 264 for storing software and data, network ports 266 fortransmitting and receiving data over a network, and an encryptionprocessor 260 for performing functions related to Secure Sockets Layerprocessing of data transmitted and received over the network. In someembodiments, the central processing unit 262 may perform the functionsof the encryption processor 260 in a single processor. Additionally, thehardware layer 206 may comprise multiple processors for each of theprocessing unit 262 and the encryption processor 260. The processor 262may include any of the processors 101 described above in connection withFIGS. 1E and 1F. In some embodiments, the central processing unit 262may perform the functions of the encryption processor 260 in a singleprocessor. Additionally, the hardware layer 206 may comprise multipleprocessors for each of the processing unit 262 and the encryptionprocessor 260. For example, in one embodiment, the appliance 200comprises a first processor 262 and a second processor 262′. In otherembodiments, the processor 262 or 262′ comprises a multi-core processor.

Although the hardware layer 206 of appliance 200 is generallyillustrated with an encryption processor 260, processor 260 may be aprocessor for performing functions related to any encryption protocol,such as the Secure Socket Layer (SSL) or Transport Layer Security (TLS)protocol. In some embodiments, the processor 260 may be a generalpurpose processor (GPP), and in further embodiments, may be haveexecutable instructions for performing processing of any securityrelated protocol.

Although the hardware layer 206 of appliance 200 is illustrated withcertain elements in FIG. 2, the hardware portions or components ofappliance 200 may comprise any type and form of elements, hardware orsoftware, of a computing device, such as the computing device 100illustrated and discussed herein in conjunction with FIGS. 1E and 1F. Insome embodiments, the appliance 200 may comprise a server, gateway,router, switch, bridge or other type of computing or network device, andhave any hardware and/or software elements associated therewith.

The operating system of appliance 200 allocates, manages, or otherwisesegregates the available system memory into kernel space 204 and userspace 204. In example software architecture 200, the operating systemmay be any type and/or form of Unix operating system although theinvention is not so limited. As such, the appliance 200 can be runningany operating system such as any of the versions of the Microsoft®Windows operating systems, the different releases of the Unix and Linuxoperating systems, any version of the Mac OS® for Macintosh computers,any embedded operating system, any network operating system, anyreal-time operating system, any open source operating system, anyproprietary operating system, any operating systems for mobile computingdevices or network devices, or any other operating system capable ofrunning on the appliance 200 and performing the operations describedherein.

The kernel space 204 is reserved for running the kernel 230, includingany device drivers, kernel extensions or other kernel related software.As known to those skilled in the art, the kernel 230 is the core of theoperating system, and provides access, control, and management ofresources and hardware-related elements of the application 104. Inaccordance with an embodiment of the appliance 200, the kernel space 204also includes a number of network services or processes working inconjunction with a cache manager 232, sometimes also referred to as theintegrated cache, the benefits of which are described in detail furtherherein. Additionally, the embodiment of the kernel 230 will depend onthe embodiment of the operating system installed, configured, orotherwise used by the device 200.

In one embodiment, the device 200 comprises one network stack 267, suchas a TCP/IP based stack, for communicating with the client 102 and/orthe server 106. In one embodiment, the network stack 267 is used tocommunicate with a first network, such as network 108, and a secondnetwork 110. In some embodiments, the device 200 terminates a firsttransport layer connection, such as a TCP connection of a client 102,and establishes a second transport layer connection to a server 106 foruse by the client 102, e.g., the second transport layer connection isterminated at the appliance 200 and the server 106. The first and secondtransport layer connections may be established via a single networkstack 267. In other embodiments, the device 200 may comprise multiplenetwork stacks, for example 267 and 267′, and the first transport layerconnection may be established or terminated at one network stack 267,and the second transport layer connection on the second network stack267′. For example, one network stack may be for receiving andtransmitting network packet on a first network, and another networkstack for receiving and transmitting network packets on a secondnetwork. In one embodiment, the network stack 267 comprises a buffer 243for queuing one or more network packets for transmission by theappliance 200.

As shown in FIG. 2, the kernel space 204 includes the cache manager 232,a high-speed layer 2-7 integrated packet engine 240, an encryptionengine 234, a policy engine 236 and multi-protocol compression logic238. Running these components or processes 232, 240, 234, 236 and 238 inkernel space 204 or kernel mode instead of the user space 202 improvesthe performance of each of these components, alone and in combination.Kernel operation means that these components or processes 232, 240, 234,236 and 238 run in the core address space of the operating system of thedevice 200. For example, running the encryption engine 234 in kernelmode improves encryption performance by moving encryption and decryptionoperations to the kernel, thereby reducing the number of transitionsbetween the memory space or a kernel thread in kernel mode and thememory space or a thread in user mode. For example, data obtained inkernel mode may not need to be passed or copied to a process or threadrunning in user mode, such as from a kernel level data structure to auser level data structure. In another aspect, the number of contextswitches between kernel mode and user mode are also reduced.Additionally, synchronization of and communications between any of thecomponents or processes 232, 240, 235, 236 and 238 can be performed moreefficiently in the kernel space 204.

In some embodiments, any portion of the components 232, 240, 234, 236and 238 may run or operate in the kernel space 204, while other portionsof these components 232, 240, 234, 236 and 238 may run or operate inuser space 202. In one embodiment, the appliance 200 uses a kernel-leveldata structure providing access to any portion of one or more networkpackets, for example, a network packet comprising a request from aclient 102 or a response from a server 106. In some embodiments, thekernel-level data structure may be obtained by the packet engine 240 viaa transport layer driver interface or filter to the network stack 267.The kernel-level data structure may comprise any interface and/or dataaccessible via the kernel space 204 related to the network stack 267,network traffic or packets received or transmitted by the network stack267. In other embodiments, the kernel-level data structure may be usedby any of the components or processes 232, 240, 234, 236 and 238 toperform the desired operation of the component or process. In oneembodiment, a component 232, 240, 234, 236 and 238 is running in kernelmode 204 when using the kernel-level data structure, while in anotherembodiment, the component 232, 240, 234, 236 and 238 is running in usermode when using the kernel-level data structure. In some embodiments,the kernel-level data structure may be copied or passed to a secondkernel-level data structure, or any desired user-level data structure.

The cache manager 232 may comprise software, hardware or any combinationof software and hardware to provide cache access, control and managementof any type and form of content, such as objects or dynamicallygenerated objects served by the originating servers 106. The data,objects or content processed and stored by the cache manager 232 maycomprise data in any format, such as a markup language, or communicatedvia any protocol. In some embodiments, the cache manager 232 duplicatesoriginal data stored elsewhere or data previously computed, generated ortransmitted, in which the original data may require longer access timeto fetch, compute or otherwise obtain relative to reading a cache memoryelement. Once the data is stored in the cache memory element, future usecan be made by accessing the cached copy rather than refetching orrecomputing the original data, thereby reducing the access time. In someembodiments, the cache memory element may comprise a data object inmemory 264 of device 200. In other embodiments, the cache memory elementmay comprise memory having a faster access time than memory 264. Inanother embodiment, the cache memory element may comprise any type andform of storage element of the device 200, such as a portion of a harddisk. In some embodiments, the processing unit 262 may provide cachememory for use by the cache manager 232. In yet further embodiments, thecache manager 232 may use any portion and combination of memory,storage, or the processing unit for caching data, objects, and othercontent.

Furthermore, the cache manager 232 includes any logic, functions, rules,or operations to perform any embodiments of the techniques of theappliance 200 described herein. For example, the cache manager 232includes logic or functionality to invalidate objects based on theexpiration of an invalidation time period or upon receipt of aninvalidation command from a client 102 or server 106. In someembodiments, the cache manager 232 may operate as a program, service,process or task executing in the kernel space 204, and in otherembodiments, in the user space 202. In one embodiment, a first portionof the cache manager 232 executes in the user space 202 while a secondportion executes in the kernel space 204. In some embodiments, the cachemanager 232 can comprise any type of general purpose processor (GPP), orany other type of integrated circuit, such as a Field Programmable GateArray (FPGA), Programmable Logic Device (PLD), or Application SpecificIntegrated Circuit (ASIC).

The policy engine 236 may include, for example, an intelligentstatistical engine or other programmable application(s). In oneembodiment, the policy engine 236 provides a configuration mechanism toallow a user to identifying, specify, define or configure a cachingpolicy. Policy engine 236, in some embodiments, also has access tomemory to support data structures such as lookup tables or hash tablesto enable user-selected caching policy decisions. In other embodiments,the policy engine 236 may comprise any logic, rules, functions oroperations to determine and provide access, control and management ofobjects, data or content being cached by the appliance 200 in additionto access, control and management of security, network traffic, networkaccess, compression or any other function or operation performed by theappliance 200. Further examples of specific caching policies are furtherdescribed herein.

The encryption engine 234 comprises any logic, business rules, functionsor operations for handling the processing of any security relatedprotocol, such as SSL or TLS, or any function related thereto. Forexample, the encryption engine 234 encrypts and decrypts networkpackets, or any portion thereof, communicated via the appliance 200. Theencryption engine 234 may also setup or establish SSL or TLS connectionson behalf of the client 102 a-102 n, server 106 a-106 n, or appliance200. As such, the encryption engine 234 provides offloading andacceleration of SSL processing. In one embodiment, the encryption engine234 uses a tunneling protocol to provide a virtual private networkbetween a client 102 a-102 n and a server 106 a-106 n. In someembodiments, the encryption engine 234 is in communication with theEncryption processor 260. In other embodiments, the encryption engine234 comprises executable instructions running on the Encryptionprocessor 260.

The multi-protocol compression engine 238 comprises any logic, businessrules, function or operations for compressing one or more protocols of anetwork packet, such as any of the protocols used by the network stack267 of the device 200. In one embodiment, multi-protocol compressionengine 238 compresses bi-directionally between clients 102 a-102 n andservers 106 a-106 n any TCP/IP based protocol, including MessagingApplication Programming Interface (MAPI) (email), File Transfer Protocol(FTP), HyperText Transfer Protocol (HTTP), Common Internet File System(CIFS) protocol (file transfer), Independent Computing Architecture(ICA) protocol, Remote Desktop Protocol (RDP), Wireless ApplicationProtocol (WAP), Mobile IP protocol, and Voice Over IP (VoIP) protocol.In other embodiments, multi-protocol compression engine 238 providescompression of Hypertext Markup Language (HTML) based protocols and insome embodiments, provides compression of any markup languages, such asthe Extensible Markup Language (XML). In one embodiment, themulti-protocol compression engine 238 provides compression of anyhigh-performance protocol, such as any protocol designed for appliance200 to appliance 200 communications. In another embodiment, themulti-protocol compression engine 238 compresses any payload of or anycommunication using a modified transport control protocol, such asTransaction TCP (T/TCP), TCP with selection acknowledgements (TCP-SACK),TCP with large windows (TCP-LW), a congestion prediction protocol suchas the TCP-Vegas protocol, and a TCP spoofing protocol.

As such, the multi-protocol compression engine 238 acceleratesperformance for users accessing applications via desktop clients, e.g.,Microsoft Outlook and non-Web thin clients, such as any client launchedby popular enterprise applications like Oracle, SAP and Siebel, and evenmobile clients, such as the Pocket PC. In some embodiments, themulti-protocol compression engine 238 by executing in the kernel mode204 and integrating with packet processing engine 240 accessing thenetwork stack 267 is able to compress any of the protocols carried bythe TCP/IP protocol, such as any application layer protocol.

High speed layer 2-7 integrated packet engine 240, also generallyreferred to as a packet processing engine or packet engine, isresponsible for managing the kernel-level processing of packets receivedand transmitted by appliance 200 via network ports 266. The high speedlayer 2-7 integrated packet engine 240 may comprise a buffer for queuingone or more network packets during processing, such as for receipt of anetwork packet or transmission of a network packer. Additionally, thehigh speed layer 2-7 integrated packet engine 240 is in communicationwith one or more network stacks 267 to send and receive network packetsvia network ports 266. The high speed layer 2-7 integrated packet engine240 works in conjunction with encryption engine 234, cache manager 232,policy engine 236 and multi-protocol compression logic 238. Inparticular, encryption engine 234 is configured to perform SSLprocessing of packets, policy engine 236 is configured to performfunctions related to traffic management such as request-level contentswitching and request-level cache redirection, and multi-protocolcompression logic 238 is configured to perform functions related tocompression and decompression of data.

The high speed layer 2-7 integrated packet engine 240 includes a packetprocessing timer 242. In one embodiment, the packet processing timer 242provides one or more time intervals to trigger the processing ofincoming, i.e., received, or outgoing, i.e., transmitted, networkpackets. In some embodiments, the high speed layer 2-7 integrated packetengine 240 processes network packets responsive to the timer 242. Thepacket processing timer 242 provides any type and form of signal to thepacket engine 240 to notify, trigger, or communicate a time relatedevent, interval or occurrence. In many embodiments, the packetprocessing timer 242 operates in the order of milliseconds, such as forexample 100 ms, 50 ms or 25 ms. For example, in some embodiments, thepacket processing timer 242 provides time intervals or otherwise causesa network packet to be processed by the high speed layer 2-7 integratedpacket engine 240 at a 10 ms time interval, while in other embodiments,at a 5 ms time interval, and still yet in further embodiments, as shortas a 3, 2, or 1 ms time interval. The high speed layer 2-7 integratedpacket engine 240 may be interfaced, integrated or in communication withthe encryption engine 234, cache manager 232, policy engine 236 andmulti-protocol compression engine 238 during operation. As such, any ofthe logic, functions, or operations of the encryption engine 234, cachemanager 232, policy engine 236 and multi-protocol compression logic 238may be performed responsive to the packet processing timer 242 and/orthe packet engine 240. Therefore, any of the logic, functions, oroperations of the encryption engine 234, cache manager 232, policyengine 236 and multi-protocol compression logic 238 may be performed atthe granularity of time intervals provided via the packet processingtimer 242, for example, at a time interval of less than or equal to 10ms. For example, in one embodiment, the cache manager 232 may performinvalidation of any cached objects responsive to the high speed layer2-7 integrated packet engine 240 and/or the packet processing timer 242.In another embodiment, the expiry or invalidation time of a cachedobject can be set to the same order of granularity as the time intervalof the packet processing timer 242, such as at every 10 ms.

In contrast to kernel space 204, user space 202 is the memory area orportion of the operating system used by user mode applications orprograms otherwise running in user mode. A user mode application may notaccess kernel space 204 directly and uses service calls in order toaccess kernel services. As shown in FIG. 2, user space 202 of appliance200 includes a graphical user interface (GUI) 210, a command lineinterface (CLI) 212, shell services 214, health monitoring program 216,and daemon services 218. GUI 210 and CLI 212 provide a means by which asystem administrator or other user can interact with and control theoperation of appliance 200, such as via the operating system of theappliance 200 and either is user space 202 or kernel space 204. The GUI210 may be any type and form of graphical user interface and may bepresented via text, graphical or otherwise, by any type of program orapplication, such as a browser. The CLI 212 may be any type and form ofcommand line or text-based interface, such as a command line provided bythe operating system. For example, the CLI 212 may comprise a shell,which is a tool to enable users to interact with the operating system.In some embodiments, the CLI 212 may be provided via a bash, csh, tcsh,or ksh type shell. The shell services 214 comprises the programs,services, tasks, processes or executable instructions to supportinteraction with the appliance 200 or operating system by a user via theGUI 210 and/or CLI 212.

Health monitoring program 216 is used to monitor, check, report andensure that network systems are functioning properly and that users arereceiving requested content over a network. Health monitoring program216 comprises one or more programs, services, tasks, processes orexecutable instructions to provide logic, rules, functions or operationsfor monitoring any activity of the appliance 200. In some embodiments,the health monitoring program 216 intercepts and inspects any networktraffic passed via the appliance 200. In other embodiments, the healthmonitoring program 216 interfaces by any suitable means and/ormechanisms with one or more of the following: the encryption engine 234,cache manager 232, policy engine 236, multi-protocol compression logic238, packet engine 240, daemon services 218, and shell services 214. Assuch, the health monitoring program 216 may call any applicationprogramming interface (API) to determine a state, status, or health ofany portion of the appliance 200. For example, the health monitoringprogram 216 may ping or send a status inquiry on a periodic basis tocheck if a program, process, service or task is active and currentlyrunning. In another example, the health monitoring program 216 may checkany status, error or history logs provided by any program, process,service or task to determine any condition, status or error with anyportion of the appliance 200.

Daemon services 218 are programs that run continuously or in thebackground and handle periodic service requests received by appliance200. In some embodiments, a daemon service may forward the requests toother programs or processes, such as another daemon service 218 asappropriate. As known to those skilled in the art, a daemon service 218may run unattended to perform continuous or periodic system widefunctions, such as network control, or to perform any desired task. Insome embodiments, one or more daemon services 218 run in the user space202, while in other embodiments, one or more daemon services 218 run inthe kernel space.

Referring now to FIG. 2B, another embodiment of the appliance 200 isdepicted. In brief overview, the appliance 200 provides one or more ofthe following services, functionality or operations: SSL VPNconnectivity 280, switching/load balancing 284, Domain Name Serviceresolution 286, acceleration 288 and an application firewall 290 forcommunications between one or more clients 102 and one or more servers106. Each of the servers 106 may provide one or more network relatedservices 270 a-270 n (referred to as services 270). For example, aserver 106 may provide an HTTP service 270. The appliance 200 comprisesone or more virtual servers or virtual internet protocol servers,referred to as a vServer, VIP server, or just VIP 275 a-275 n (alsoreferred herein as vServer 275). The vServer 275 receives, intercepts orotherwise processes communications between a client 102 and a server 106in accordance with the configuration and operations of the appliance200.

The vServer 275 may comprise software, hardware or any combination ofsoftware and hardware. The vServer 275 may comprise any type and form ofprogram, service, task, process or executable instructions operating inuser mode 202, kernel mode 204 or any combination thereof in theappliance 200. The vServer 275 includes any logic, functions, rules, oroperations to perform any embodiments of the techniques describedherein, such as SSL VPN 280, switching/load balancing 284, Domain NameService resolution 286, acceleration 288 and an application firewall290. In some embodiments, the vServer 275 establishes a connection to aservice 270 of a server 106. The service 275 may comprise any program,application, process, task or set of executable instructions capable ofconnecting to and communicating to the appliance 200, client 102 orvServer 275. For example, the service 275 may comprise a web server,HTTP server, ftp, email or database server. In some embodiments, theservice 270 is a daemon process or network driver for listening,receiving and/or sending communications for an application, such asemail, database or an enterprise application. In some embodiments, theservice 270 may communicate on a specific IP address, or IP address andport.

In some embodiments, the vServer 275 applies one or more policies of thepolicy engine 236 to network communications between the client 102 andserver 106. In one embodiment, the policies are associated with aVServer 275. In another embodiment, the policies are based on a user, ora group of users. In yet another embodiment, a policy is global andapplies to one or more vServers 275 a-275 n, and any user or group ofusers communicating via the appliance 200. In some embodiments, thepolicies of the policy engine have conditions upon which the policy isapplied based on any content of the communication, such as internetprotocol address, port, protocol type, header or fields in a packet, orthe context of the communication, such as user, group of the user,vServer 275, transport layer connection, and/or identification orattributes of the client 102 or server 106.

In other embodiments, the appliance 200 communicates or interfaces withthe policy engine 236 to determine authentication and/or authorizationof a remote user or a remote client 102 to access the computingenvironment 15, application, and/or data file from a server 106. Inanother embodiment, the appliance 200 communicates or interfaces withthe policy engine 236 to determine authentication and/or authorizationof a remote user or a remote client 102 to have the application deliverysystem 190 deliver one or more of the computing environment 15,application, and/or data file. In yet another embodiment, the appliance200 establishes a VPN or SSL VPN connection based on the policy engine's236 authentication and/or authorization of a remote user or a remoteclient 103 In one embodiment, the appliance 102 controls the flow ofnetwork traffic and communication sessions based on policies of thepolicy engine 236. For example, the appliance 200 may control the accessto a computing environment 15, application or data file based on thepolicy engine 236.

In some embodiments, the vServer 275 establishes a transport layerconnection, such as a TCP or UDP connection with a client 102 via theclient agent 120. In one embodiment, the vServer 275 listens for andreceives communications from the client 102. In other embodiments, thevServer 275 establishes a transport layer connection, such as a TCP orUDP connection with a client server 106. In one embodiment, the vServer275 establishes the transport layer connection to an internet protocoladdress and port of a server 270 running on the server 106. In anotherembodiment, the vServer 275 associates a first transport layerconnection to a client 102 with a second transport layer connection tothe server 106. In some embodiments, a vServer 275 establishes a pool oftransport layer connections to a server 106 and multiplexes clientrequests via the pooled transport layer connections.

In some embodiments, the appliance 200 provides a SSL VPN connection 280between a client 102 and a server 106. For example, a client 102 on afirst network 102 requests to establish a connection to a server 106 ona second network 104′. In some embodiments, the second network 104′ isnot routable from the first network 104. In other embodiments, theclient 102 is on a public network 104 and the server 106 is on a privatenetwork 104′, such as a corporate network. In one embodiment, the clientagent 120 intercepts communications of the client 102 on the firstnetwork 104, encrypts the communications, and transmits thecommunications via a first transport layer connection to the appliance200. The appliance 200 associates the first transport layer connectionon the first network 104 to a second transport layer connection to theserver 106 on the second network 104. The appliance 200 receives theintercepted communication from the client agent 102, decrypts thecommunications, and transmits the communication to the server 106 on thesecond network 104 via the second transport layer connection. The secondtransport layer connection may be a pooled transport layer connection.As such, the appliance 200 provides an end-to-end secure transport layerconnection for the client 102 between the two networks 104, 104′.

A virtual private network (VPN) may be any network using publictelecommunication infrastructure, such as the internet, to provideremote clients, servers or other communicating devices with an access orconnection into a private network, such as from a public network. Avirtual private network (VPN) is a way to use a public telecommunicationinfrastructure, such as the Internet, to provide remote users withaccess to an enterprise or private network. In some embodiments, theaccess is secure via encryption or tunneling. In some embodiments, theintermediary described herein provides a secure virtual private networkconnection from a first network of the client to the second network ofthe server.

A Secure Socket Layer (SSL) VPN may use SSL or TLS or any other type andform of secure protocols to establish the connection with a level ofsecurity. In some embodiments, an SSL VPN may use any type and form ofencryption for establishing or maintaining secure access. An SSL VPN maybe established and/or accessed via a browser such as using HTTPS (SecureHyperText Transfer Protocol). An SSL VPN may be established or providedby an SSL enabled browser or application.

The SSL VPN connection or session may be established or provided byeither using a client based or clientless approach A client based SSLVPN may be use any type and form of client agent or any software relatedagent on the client 102 to establish a SSL VPN connection or session.For example, a client based SSL VPN may be provided via an SSL VPNclient agent downloaded to the client, such as downloaded from anappliance. The client agent may be designed and configured to establishand provide the SSL VPN functionality, connection and access between theclient and the appliance or server.

A clientless SSL VPN may be any SSL VPN that does not use an SSL VPNclient agent, software or programs downloaded and installed on theclient 102 to establish the SSL VPN connection or session. In someembodiments, a clientless SSL VPN may be any SSL VPN that does notrequire a client 102 to install or execute a predetermined software oran executable file designed and constructed to provide SSL VPNfunctionality in order to establish an SSL VPN connection with anothernetwork device. In some embodiments, a clientless SSL VPN is establishedvia an SSL enabled browser that has not downloaded or does not requirethe use of a VPN or SSL VPN client agent. A clientless SSL VPNconnection or session may use the protocols and communications of astandard browser or application, such as an SSL enabled browser. Aclientless SSL VPN connection or session may be provided by anintermediary or appliance as described herein that translates, rewritesor transforms content of requests and responses between a first networkand a second network.

In one embodiment, the appliance 200 hosts an intranet internet protocolor intranetIP 282 address of the client 102 on the virtual privatenetwork 104. The client 102 has a local network identifier, such as aninternet protocol (IP) address and/or host name on the first network104. When connected to the second network 104′ via the appliance 200,the appliance 200 establishes, assigns or otherwise provides anIntranetIP, which is network identifier, such as IP address and/or hostname, for the client 102 on the second network 104′. The appliance 200listens for and receives on the second or private network 104′ for anycommunications directed towards the client 102 using the client'sestablished IntranetIP 282. In one embodiment, the appliance 200 acts asor on behalf of the client 102 on the second private network 104. Forexample, in another embodiment, a vServer 275 listens for and respondsto communications to the IntranetIP 282 of the client 102. In someembodiments, if a computing device 100 on the second network 104′transmits a request, the appliance 200 processes the request as if itwere the client 102. For example, the appliance 200 may respond to aping to the client's IntranetIP 282. In another example, the appliancemay establish a connection, such as a TCP or UDP connection, withcomputing device 100 on the second network 104 requesting a connectionwith the client's IntranetIP 282.

In some embodiments, the appliance 200 provides one or more of thefollowing acceleration techniques 288 to communications between theclient 102 and server 106: 1) compression; 2) decompression; 3)Transmission Control Protocol pooling; 4) Transmission Control Protocolmultiplexing; 5) Transmission Control Protocol buffering; and 6)caching. In one embodiment, the appliance 200 relieves servers 106 ofmuch of the processing load caused by repeatedly opening and closingtransport layers connections to clients 102 by opening one or moretransport layer connections with each server 106 and maintaining theseconnections to allow repeated data accesses by clients via the Internet.This technique is referred to herein as “connection pooling”.

In some embodiments, in order to seamlessly splice communications from aclient 102 to a server 106 via a pooled transport layer connection, theappliance 200 translates or multiplexes communications by modifyingsequence number and acknowledgment numbers at the transport layerprotocol level. This is referred to as “connection multiplexing”. Insome embodiments, no application layer protocol interaction is required.For example, in the case of an in-bound packet (that is, a packetreceived from a client 102), the source network address of the packet ischanged to that of an output port of appliance 200, and the destinationnetwork address is changed to that of the intended server. In the caseof an outbound packet (that is, one received from a server 106), thesource network address is changed from that of the server 106 to that ofan output port of appliance 200 and the destination address is changedfrom that of appliance 200 to that of the requesting client 102. Thesequence numbers and acknowledgment numbers of the packet are alsotranslated to sequence numbers and acknowledgement expected by theclient 102 on the appliance's 200 transport layer connection to theclient 102. In some embodiments, the packet checksum of the transportlayer protocol is recalculated to account for these translations.

In another embodiment, the appliance 200 provides switching orload-balancing functionality 284 for communications between the client102 and server 106. In some embodiments, the appliance 200 distributestraffic and directs client requests to a server 106 based on layer 4 orapplication-layer request data. In one embodiment, although the networklayer or layer 2 of the network packet identifies a destination server106, the appliance 200 determines the server 106 to distribute thenetwork packet by application information and data carried as payload ofthe transport layer packet. In one embodiment, the health monitoringprograms 216 of the appliance 200 monitor the health of servers todetermine the server 106 for which to distribute a client's request. Insome embodiments, if the appliance 200 detects a server 106 is notavailable or has a load over a predetermined threshold, the appliance200 can direct or distribute client requests to another server 106.

In some embodiments, the appliance 200 acts as a Domain Name Service(DNS) resolver or otherwise provides resolution of a DNS request fromclients 102. In some embodiments, the appliance intercepts' a DNSrequest transmitted by the client 102. In one embodiment, the appliance200 responds to a client's DNS request with an IP address of or hostedby the appliance 200. In this embodiment, the client 102 transmitsnetwork communication for the domain name to the appliance 200. Inanother embodiment, the appliance 200 responds to a client's DNS requestwith an IP address of or hosted by a second appliance 200′. In someembodiments, the appliance 200 responds to a client's DNS request withan IP address of a server 106 determined by the appliance 200.

In yet another embodiment, the appliance 200 provides applicationfirewall functionality 290 for communications between the client 102 andserver 106. In one embodiment, the policy engine 236 provides rules fordetecting and blocking illegitimate requests. In some embodiments, theapplication firewall 290 protects against denial of service (DoS)attacks. In other embodiments, the appliance inspects the content ofintercepted requests to identify and block application-based attacks. Insome embodiments, the rules/policy engine 236 comprises one or moreapplication firewall or security control policies for providingprotections against various classes and types of web or Internet basedvulnerabilities, such as one or more of the following: 1) bufferoverflow, 2) CGI-BIN parameter manipulation, 3) form/hidden fieldmanipulation, 4) forceful browsing, 5) cookie or session poisoning, 6)broken access control list (ACLs) or weak passwords, 7) cross-sitescripting (XSS), 8) command injection, 9) SQL injection, 10) errortriggering sensitive information leak, 11) insecure use of cryptography,12) server misconfiguration, 13) back doors and debug options, 14)website defacement, 15) platform or operating systems vulnerabilities,and 16) zero-day exploits. In an embodiment, the application firewall290 provides HTML form field protection in the form of inspecting oranalyzing the network communication for one or more of the following: 1)required fields are returned, 2) no added field allowed, 3) read-onlyand hidden field enforcement, 4) drop-down list and radio button fieldconformance, and 5) form-field max-length enforcement. In someembodiments, the application firewall 290 ensures cookies are notmodified. In other embodiments, the application firewall 290 protectsagainst forceful browsing by enforcing legal URLs.

In still yet other embodiments, the application firewall 290 protectsany confidential information contained in the network communication. Theapplication firewall 290 may inspect or analyze any networkcommunication in accordance with the rules or polices of the engine 236to identify any confidential information in any field of the networkpacket. In some embodiments, the application firewall 290 identifies inthe network communication one or more occurrences of a credit cardnumber, password, social security number, name, patient code, contactinformation, and age. The encoded portion of the network communicationmay comprise these occurrences or the confidential information. Based onthese occurrences, in one embodiment, the application firewall 290 maytake a policy action on the network communication, such as preventtransmission of the network communication. In another embodiment, theapplication firewall 290 may rewrite, remove or otherwise mask suchidentified occurrence or confidential information.

Still referring to FIG. 2B, the appliance 200 may include a performancemonitoring agent 197 as discussed above in conjunction with FIG. 1D. Inone embodiment, the appliance 200 receives the monitoring agent 197 fromthe monitoring service 1908 or monitoring server 106 as depicted in FIG.1D. In some embodiments, the appliance 200 stores the monitoring agent197 in storage, such as disk, for delivery to any client or server incommunication with the appliance 200. For example, in one embodiment,the appliance 200 transmits the monitoring agent 197 to a client uponreceiving a request to establish a transport layer connection. In otherembodiments, the appliance 200 transmits the monitoring agent 197 uponestablishing the transport layer connection with the client 102. Inanother embodiment, the appliance 200 transmits the monitoring agent 197to the client upon intercepting or detecting a request for a web page.In yet another embodiment, the appliance 200 transmits the monitoringagent 197 to a client or a server in response to a request from themonitoring server 198. In one embodiment, the appliance 200 transmitsthe monitoring agent 197 to a second appliance 200′ or appliance 205.

In other embodiments, the appliance 200 executes the monitoring agent197. In one embodiment, the monitoring agent 197 measures and monitorsthe performance of any application, program, process, service, task orthread executing on the appliance 200. For example, the monitoring agent197 may monitor and measure performance and operation of vServers275A-275N. In another embodiment, the monitoring agent 197 measures andmonitors the performance of any transport layer connections of theappliance 200. In some embodiments, the monitoring agent 197 measuresand monitors the performance of any user sessions traversing theappliance 200. In one embodiment, the monitoring agent 197 measures andmonitors the performance of any virtual private network connectionsand/or sessions traversing the appliance 200, such an SSL VPN session.In still further embodiments, the monitoring agent 197 measures andmonitors the memory, CPU and disk usage and performance of the appliance200. In yet another embodiment, the monitoring agent 197 measures andmonitors the performance of any acceleration technique 288 performed bythe appliance 200, such as SSL offloading, connection pooling andmultiplexing, caching, and compression. In some embodiments, themonitoring agent 197 measures and monitors the performance of any loadbalancing and/or content switching 284 performed by the appliance 200.In other embodiments, the monitoring agent 197 measures and monitors theperformance of application firewall 290 protection and processingperformed by the appliance 200.

C. Clientless Virtual Private Network Environment

Referring now to FIG. 3A, an embodiment of a clientless virtual privatenetwork (VPN) environment for accessing a server via an appliance 200 orproxy is depicted. In brief overview, the client 102 operates oncomputing device 100 and executes a browser operated by a user. Theclient 102 may be on a first network 104, such as a public network. Auser on the client 102 may request via the browser access to a resourceon a second network 104′, such as a private network of an enterprise.The appliance 200 provides the user a clientless VPN access to therequested resource. The client may not install, execute or otherwise anyagent, component, program, driver or application that is constructedand/or designed to provide VPN connectivity (referred to as client basedVPN) to the network 104′. Instead, the appliance or proxy may rewriteresponses from the server and requests from the client to provide VPNfunctionality without the user of a VPN agent operating on the client.For example, the appliance may rewrite Uniform Resource Locators (URLs)between the client and server, such as URLs in any content server by theserver or requests transmitted by the client. The appliance 200 mayrewrite URLs between the client and the server in a manner transparentand seamless to either or both of the client and the server. As such,the client, browser or server and server application do not need to haveknowledge or be aware of the clientless SSL VPN access scenario.

The appliance 200 may provide via an SSL VPN 280 module, previouslydescribed herein, a facility for accessing a resource. In oneembodiment, the appliance 200 provides a client based access to anetwork by providing, installing or executing an SSL VPN agent on theclient 102 for communicating with the appliance 200. In someembodiments, the appliance 200 provides for clientless SSL VPN access toa resource, such as an http/https/file share, without having to downloadan SSL VPN client or agent to the client 102. For example, a user maywant to access the resources within company from an outside machine suchat a kiosk on which he does not have privilege to install the client ordoes not want to go through the client installation process. Theclientless SSL VPN feature is also useful when the SSL VPN client is notsupported for the device (e.g. new PDA in market) but the device run anSSL enabled browser. In other embodiments, the appliance 200 chooses fora user between client-based and clientless SSL VPN access to theresource based on policy and any policy rules, actions and/orconditions.

The client may include any type and form of user agent which may be abrowser, editor, spider (web-traversing robots), or any other end usertool or program. The client 102 may include any type and form ofbrowser. In one embodiment, the browser is any version of InternetExplorer manufactured by Microsoft Corporation of Redmond, Wash. Inanother embodiment, the browser is any version of the Netscape browsermanufactured by the Netscape Communications Corporation. In otherembodiments, the browser is any version of the open source browserreferred to as Firefox and provided by Mozilla Foundation of Californiaand found at www.mozilla.com. In yet another embodiment, the browser isany version of the browser referred to as Opera manufactured by OperaSoftware ASA of Oslo, Norway. In some embodiments, the client 102executes or includes any type and form of application or program fordisplaying web pages, web content, HTML, XML, CSS (Cascading StyleSheets), JavaScript or HTTP content.

In operation of the embodiment depicted by FIG. 3A, a user logs in atthe SSL VPN site provided by the appliance 200, such at a domain nameand IP address hosted by the appliance 200. For example, the user via abrowser of the client 102, may select or enter a URL to the SSL VPNsite. The appliance 200 may authenticate the user and may furtherdetermine authorization of the user to access the appliance 200 or theSSL VPN site. After successful authentication, the appliance serves aportal page to the client to display to the user via the browser. Theportal page may include a navigation box, such as a set of one or moreuser interface elements for a user to select to operate or run anapplication. The portal page may include links to other pages or URLs towhich the user may have access. The URLs or links on the portal page mayreference or identify the host name or IP address of the SSL VPN siteprovided by the appliance 200.

The user via the portal page may select one or more URLs, for example,by clicking on an active hyperlink or URL. In response, the browser orclient transmits a request to the domain hosted by the appliance 200.For example, as depicted in FIG. 3A, the user may request an applicationof the server 106 via the appliance:“https://sslvpn.x.com/cvpn/http/server.x.com/app.cgi”. In someembodiments, the user sends another request, such as for example“https://proxy.x.com/cvpn/http/server.x.com/app.cgi”. The appliance 200receives the request from the client 102 and rewrites the request totransmit to the server. For example, as depicted in FIG. 3A, theappliance may remove or strip the domain name hosted by the appliancesuch as “sslvpn.x.com” or “proxy.x.com” and forward the remainingportion of the request to the server 106.

In response to the request, the server serves content to the client. Thecontent or body of the response may include embedded links or URLs toother pages of the server or to other servers on the network 104′, suchas embedded links to “http://server.x.com/app.cgi”. The appliancerewrites the header and body to modify any URLs to reference the domainname or IP address of the SSL VPN site so that any further URL or linkselection via the browser of the client communicates requests to theappliance 200. The appliance communicates the modified content to theclient 102. The appliance 200, such as via the AppFw 290, sometimesreferred to as AppSecure module 290, may be designed and constructed torewrite URLs of requests and responses based on policy of a policyengine. The links (URLs) in that page and other pages receivedsubsequently from the server during this SSL VPN session are modified bythe appliance in such a way that the links point to the SSL VPN site(VPN VIP 275) and the original request URL (absolute or relative) isencoded within that request URL.

Referring now to FIG. 3B, another embodiment of a VPN environment forproviding VPN access as well as cookie management is depicted. In briefoverview, the appliance 200 may include a VPN module 280 for handlingany of the SSL VPN functionality, clientless and/or client based, asdescribed herein. The appliance and/or VPN module 280 may have an AAAmodule to perform any type and form of authentication, authorization andauditing (AAA) and/or to track and manage VPN session information. TheAAA module may also perform any type and form of VPN session look todetermine the VPN session for any client request. The VPN module mayalso perform an URL decoding and covert the URL to server format, suchas to submit to a server on the private network. VPN module 280 alsoincludes DNS lookup functionality and authorization via VPN handlerfunction, logic or operation.

The appliance may include a cookie proxy or cookie manager for storing,tracking and managing cookies between the client and the server. Thecookie may include cookie storage, referred to as a cookie jar foradding or inserting cookies as well as removing cookies. The cookiemanager or proxy may include functions, logic or operations to store andlook up cookie information in a cookie jar by URL, domain name or otherinformation of the request and/or response. In some embodiments, theappliance 200 manages cookies on the behalf of clients that do notsupport cookies, disabled cookies or for cases where it may be desiredor preferred not to send cookies to the client.

The appliance may also include an AppFW 280 also referred to asAppSecure in the context of an appliance manufactured by Citrix Systems,Inc. The AppSecure 280 module may include logic, functions or operationsfor perform any type and form of content rewriting, such as URLrewriting. In some embodiments, the AppSecure 280 module performs anytype and form of content injection into a request and/or responsebetween a client and a server. In one embodiment, the AppSecure module280 injects scripts into a response to the client, such as a JavaScript,to perform any type and form of desired functionality.

Any of the components of the appliance 200 used for clientless SSL VPNaccess may be responsive to or driven by configuration, such as via anyone or more policies of the policy engine. The policies may direct anddetermine the type and form of URL encoding and decoding performed bythe VPN module. In some embodiments, the policies may direct anddetermine how and when the cookie proxy manages and proxies cookies. Inother embodiments, the policies may direct and determine how and whenthe AppSecure module performs URL rewriting and/or content injection.The policies may direct the way a user access the private network andapplications on the private networks. Policies may be configured basedon access scenarios, which can include access based on any combinationof a user, type and form of client, type and form of network, type ofresources accessed, types of applications used, temporal information aswell as any information that may be determined by the appliance vianetwork traffic traversing thereto.

With reference to FIG. 3B, a flow of packets via the appliance 200 forclientless SSL VPN access is discussed. In response to a successfullogin request, the VPN appliance may send a portal page to the sender ofthe login request. The portal page may have one or more links in “vpnencoded form” as described in connection with FIG. 3A. The portal pageflows through the response code path described below. When a user clickson any of the URLs in the portal page, the packet flow may beimplemented in a number of ways and using a number of steps. In someembodiments, for request path at step Q1, the appliance 200 may receivea URL request and look up the VPN session in the AAA module. At step Q2,the appliance may decode the VPN encoded URL to the expected URL for theserver or the network 104′. The appliance may also modify the header ofthe request, such as the header values, to server format, or a formatintended for transmission and use by the server 106, such as the HTTPserver for example. The appliance may reparse the header so that anyother modules of the appliance see the request in the server format. Atstep Q3 in the request path, the appliance via the cookie manager orproxy may look up the cookie for the request based on the domain andpath of the URL. In some cases, if the request should include a cookie,the appliance may insert the cookie from a cookie jar. At step Q4, theappliance may resolve the domain name of the server present in the URLinto an IP address of the server via a DNS lookup function/module of theappliance. The appliance may create server information based on the DNSlookup in the AAA module. In addition, authorization policies may beevaluated to determine if the request may be transmitted to the server.At step Q5 the appliance may send the request to the server. In someembodiments, the appliance sends the request to the server provided thatthe authorization is successful.

In the response path from the server to the client via the appliance, atstep S1, the appliance may receive the response from the server. The VPNmodule 280 may process the response. The VPN module may pass theresponse header to the cookie proxy module and the response body to theAppSecure module. At step S2, the cookie proxy may remove cookies fromthe header of the response that are not configured or otherwiseidentified as client consumed cookies and store them in a cookie jarused for the current session. At step S3, the AppSecure module mayrewrite any URL in “vpn encoded form” as per rewrite policies. TheAppSecure module may also insert into the response body any scripts,such as JavaScript code to be executed at client side. At step S4, theappliance may send the modified response to the client. In manyembodiments, any of the Q or S steps happen in any order or in anycombination with any other steps or embodiments described herein.

D. Systems and Methods for Fine Grain Policy Driven Cookie Proxying

Cookies may be used for maintaining a state of a system or a memory of aprevious event, transaction or communication between two entities on anetwork. In some cases, cookies may be utilized for various types ofsession tracking. Cookie management may be referred to as a feature of anetwork device, such as an intermediary 200, and may provide a way tomanage a server 102 or a client 106 in creating, utilizing orcontrolling cookies transmitted between the server 106 and the client102. Embodiments of the intermediary described herein provide ways tomanage cookies for the client and the server. In some embodiments, theintermediary manages server consumed cookies on the server-side whilenot sending cookies to the client browser.

Systems and methods for cookie proxying are illustrated by FIG. 4A, FIG.4B and FIG. 4C. FIG. 4A depicts an embodiment of a system and a methodfor managing cookies in an embodiment of a clientless SSL VPNenvironment. FIG. 4B illustrates sequence diagrams and steps of anembodiment of a method for cookie management that includes a SSL VPNclientless access scenario. FIG. 4C depicts embodiments for cookieproxying by an intermediary that utilizes a unique identifier, such as aunique client ID. These illustrations may relate to a number ofembodiments of systems and methods for implementing cookie management,such as a clientless cookie management.

Clientless cookie management may enable a web client that resides withinan unsecured network to access a web application hosted behind a securednetwork without compromising the security of the secured network. Forexample, clientless cookie management may improve security for thetransmitted information by removing server consumed cookie data.Clientless cookie management may disable the server consumed cookie datafrom being transmitted to the client and prevent accessibility to anysensitive information which may be included in the cookie. In addition,clientless cookie management may enable web browsers that do not supportcookies, such as PDAs and WAP browsers to work with web applications onthe servers that require cookies. Furthermore, in instances when webapplications used are not compatible with cookie path rewriting,clientless cookie management may provide a service allowing suchapplications to function by rewriting the cookie path.

Referring now to FIG. 4A, an embodiment of a system and method forimplementing SSL VPN clientless cookie management via an intermediary200 is illustrated. FIG. 4A depicts a client 102 communicating with aserver 106 via an intermediary 200. The intermediary 200 includes apolicy engine 236 and a cookie manager 420. Client 102 transmits arequest, such as an HTTP (hypertext transfer protocol) request intendedfor the server 106 to the intermediary 200. The request includes a URL(uniform resource locator) which may identify a service or a resourcestored on or otherwise available from a server 106. Cookie manager 420receives the request and generates a cookie associated with the client102 using the policy engine 236. The generated cookie may satisfy anypreferences or configurations of the server 106, thus enabling theinitially cookie-less request to be accepted and processed by the server106. Cookie manager 420 modifies the request to include the cookieforwards the modified request to the server 106. Server 106 issues aresponse to the request and transmits the response to the intermediary200 using the cookie generated by the cookie manager 420. Cookie manager420 modifies the response by removing the cookie. The modified responseis then transmitted to the client 102. The server 106 and client 102 mayfurther transmit additional requests and responses using the cookie,thus allowing the cookie-less client 102 to access the resources on thecookie-configured server 106.

A cookie manager 420 may be any device, component, unit, function or anapparatus generating, terminating, modifying or managing cookies. Cookiemanager 420 may also modify requests of the clients 102 and responses ofthe servers 106. Cookie manager 420 may comprise hardware, software, orany combination of hardware and software components to manage andcontrol cookies. A cookie manager 420 may comprise logic, controlfunctions, processing circuitry, software programs, algorithms andscripts to control, manage or modify transmission between the clients102 and servers 106. In a number of embodiments, cookie manager 420comprises policies utilized during the process of managing cookies andproviding the control of communications between the client 102 and theserver 106.

In some embodiments, cookie manager 420 may uniquely identify a user ona network, for example by providing a unique identifier using aconfigured policy, such as a policy of a policy engine 236. Uniqueidentifier may be any number, value or a set of data, numbers orcharacters uniquely identifying a client 102, a server 106 or anappliance 200 on the network. In some embodiments, cookie manager 420may utilize the unique identifier to associate a received response fromthe server 106 with the specific client 102 to which the response isintended. Cookie manager 420 may include any functionality to modify theresponse using the cookies and client identifiers such that the client102 receives the response in a desired format. Similarly, cookie manager420 may include any functionality to modify the request of a specificclient 102 to include a specific cookie to access a resource on theserver 106 using the client unique identifier and the cookie generatedfor the client.

Cookie manager 420 may modify or change any transmission sent by aserver 106 or a client 102. In some embodiments, cookie manager 420modifies transmissions between the client 102 and server 106 using oneor more policies for handling cookies of a policy engine 236. Cookiemanager 420 may modify the transmissions to include or exclude thecookies and unique client identifiers. In some embodiments, cookiemanager 420 generates cookies for any client 102 requesting access toany servers 106. Cookie manager 420 may generate the cookie for theclients 102 in response to a policy. In some embodiments, cookie managermay determine that a particular client should not be allowed a cookie inresponse to a policy. In other embodiments, cookie manager 420determines that a particular unique client identifier should beassociated with the client 102 in response to a policy. In furtherembodiments, cookie manager 420 determines a type and form of the cookieto generate for the request in response to a policy. In yet furtherembodiments, cookie manager determines if and how will the cookies bestored for the future requests of the client in response to a policy.

In some embodiments, cookie manager eliminates or strips the cookiesfrom the requests or the responses. Cookie manager may assign orreassign cookies to the clients 102 or servers 106. In still furtherembodiments, cookie manager 420 changes, modifies or rewrite cookiesfrom the requests from the clients 102 or responses from the servers106. Cookie manager 420 may match a value, a name or a unique clientidentifier uniquely identifying a client to a cookie or a portion of thecookie associated with a client, a server or an intermediary 200. Insome embodiments, cookie manager 420 may add a cookie associated withthe unique client identifier to the URL. In further embodiments, cookiemanager 420 may remove the unique client identifier and add a cookieassociated with the unique client identifier instead. In a number ofembodiments, cookie manager 420 may replace a cookie with a uniqueidentifier, sometimes also referred to as a unique ID uniquelyidentifying a client 102 or a server 106.

The cookie manager 420 may use a parser for parsing the transmissions.Cookie manager 420 may also use an internal map for matching a pluralityof unique identifiers relating a plurality of clients, servers orappliances 200 to a plurality of cookies relating the clients, serversor the appliances. For example, the cookie manager 420 may utilize a mapcomprising a unique identifier associated with one or more cookies formatching a client 102 uniquely identified by the unique identifier withthe one or more cookies. In such cases, the cookie manager 420 maymodify, change or edit a request from the client or a response to theclient using the one or more cookies matched to the unique clientidentifier. Cookie manager 420 may utilize policies to managetransmissions between a client 102 and a server 106 by managing, addingor removing of the cookies and unique client identifiers to and from thetransmissions of the clients 102 and servers 106 as necessary to complywith configurations or preferences of receiving devices, i.e. theclients 102 and servers 106 receiving the transmissions.

A semi-colon client delimited list may be any map, list, database orfile comprising a list of cookies along with information associated withclients 102 that communicate with one or more servers 106 via theintermediary 200. Semi-colon client delimited list herein may also beinterchangeably referred to as an internal map or a list of cookies orthe map. In some embodiments, the semi-colon client delimited listcomprises name value pairs of cookies and values or unique identifierswhich may be used instead of the cookies for upstream communication,i.e. communication towards the server 106, or downstream communication,i.e. communication towards the client 102. Sometimes, cookie manager 420may use a semi-colon delimited list of the client consumed cookiesand/or the client and server consumed cookies to link, match orassociate values or unique identifiers of or more clients 102 to each ofthe cookies associated with the clients. By using the semi-colondelimited list, the cookie manager 420 may determine which cookies tore-inject, add or include into the downstream or upstream transmission.Cookie manager 420 may use the map or list of cookies to match a cookiefrom a transmission received by the intermediary 200 to the client 102to whom the transmission is destined for. The cookie manager 420 maythen edit or modify the transmission to exclude the cookie and includeany other information associated with the client 102 instead. Similarly,cookie manager 420 may use the map or the list of cookies to match aunique client identifier with a cookie to include into the transmission.

In some instances, by turning on server side cookie management and notspecifying the semi-colon delimited list, web applications may functionincorrectly. Using the semi-colon delimited list may disable this errorwhich may occur when a cookie manager 420 filters the client consumedcookies at the server 106. Using the semi-colon delimited list may alsodisable the error which may occur when a web application attempts toaccess a cookie value on the client 102 resulting in an unexpectedbehavior. In a number of embodiments, the delimited client cookie list,or the list, may comprise various on/off settings for server side orclient side cookie management. In some embodiments, the delimited clientcookie list may be stored in any number of data-layers or in varioustables comprising settings and configurations for any variable at eachstep of the method or process.

Cookies may be classified by types or characteristics. Cookie manager420 may classify or sort cookies by unique identifiers associated withthe cookies. A server consumed cookie may be a cookie set by a resource,such as a server 106, issuing a Set-Cookie on the response. The serverconsumed cookie's values may be checked or may be not checked by anyclient side code. In certain embodiments, cookie manager 420 mayidentify or classify a server consumed cookie as a server consumedcookie. In a number of embodiments, cookie manager 420 may remove aserver consumed cookie from a downstream transmission of a request or aresponse and re-inject them into an upstream transmission which isrelated to the request or the response. In other embodiments, serverconsumed cookies may be associated with confidential or sensitive datapertaining to sessions. In some embodiments, server consumed cookies maybe managed by a cookie manager 420 and may not be sent to a web browser.In certain embodiments, server consumed cookies may be stripped from themessage being sent to the web browser and may be stored in the cookiemanager 420 or any storage device related to the cookie manager 420.

A client consumed cookie may be a cookie such as a cookie that is set onan upstream transmission by a client 102's web browser via a script suchas JavaScript. In some embodiments, a client consumed cookie is a cookiethat is set on a downstream transmission from the source, where thesource may be a client 102, a server 106 or an appliance 200. In aplurality of embodiments, a client consumed cookie may be checked ormodified by the client 102 or the intermediary 200. In some embodiments,client consumed cookies are not checked or modified by the server 106.The server 106 may only accept the requests as they are and may rely onthe intermediary 200 to provide the modification to the requests.Similarly, clients 102 may also not modify responses, but may insteadrely on the intermediary 200 to modify the responses. In someembodiments, client consumed cookies are checked, edited or modified bythe server 106. In further embodiments, a client consumed cookie is notmanaged by the cookie manager 420, but is instead sent downstream to theweb browser of the client 102 instead. Sometimes, client consumedcookies and server consumed cookies may be read, modified and generatedby both the client 102 and the server 106. In some embodiments, cookiemanager 420 may not manage a client or server consumed cookie, andclient or server consumed cookies may be sent downstream toward the webbrowser of the client 102. In some embodiments, a client 102 may performthe functionality of a server 106, and vice versa. In other embodiments,a client 102 may be used interchangeably instead of a server 106, and aserver 106 may be used interchangeably instead of a client 102. In someembodiments, client or server consumed cookies may be used, modified,read, written transmitted to or from any one of the client 102, server106 or an intermediary 200. In many embodiments, server consumed cookiescomprise all functionality of client consumed cookies and may betreated, modified, controlled or otherwise used in the same way and bysame components as any client consumed cookies. Sometimes, all cookiesmay be server consumed cookies. The server consumed cookies may be used,read or edited by the server. In further embodiments, some serverconsumed cookies are also client consumed cookies. The client consumedcookies may be used, read or edited by the client in addition to beingused, read or edited by the server. In some embodiments, the server andclient consumed cookies are used, edited, read, written to, or modifiedby the intermediary 200. Sometimes in some embodiments, some cookies areused by the client and not used by the server.

The upstream or the downstream communication may be used to indicate thedirection of the communication. For example, sometimes the upstreamrequest communication or the upstream direction may relate to acommunication or transaction from the client 102 toward the server 106.In some embodiments, upstream request communication or the upstreamdirection may relate to communication or transactions from the server106 to the client 102. In a number of embodiments, the downstreamrequest communication or the downstream direction may, in someembodiments, relate to communication, transactions or direction from theclient 102 toward the server 106. In a plurality of embodiments,downstream request communication or the downstream direction may relateto communication or transactions from the server 106 to the client 102.Sometimes, transactions or communication headed toward the server may bereferred to as an upstream transaction or upstream communication andtransactions or communication headed toward the client may be referredto as a downstream transaction or downstream communication.

Further referring to FIG. 4A, steps of a method for implementing anembodiment of clientless cookie management is illustrated. At step one,the client 102 sends a request through the intermediary 200 to server106. The request comprises a URL request, such as a URL provided by theintermediary 200, for example http://abc.com/dir/index.asp. At step two,the intermediary 200 communicates with the cookie manager 420 whichchecks the incoming request URL against an internal map of cookiesavailable for the domain name and the path provided by the URL. If thecookie manager detects any matches between the incoming request URL andthe cookies available in the internal map, an array of name value pairsis returned from the cookie manager to the intermediary. At step three,the intermediary forwards the modified request to the server 106. Insome embodiments, the request may also be referred to as HTTP request,and the modified request may be referred to modified HTTP request. Therequest may be modified to include one or more cookies from the cookiemanager 420. Illustrated in FIG. 4A, the message sent in step threecomprises a value of 25 assigned to the cookie. At step four, the serverresponds to the request with a response including a header and body,such as an HTTP header and a content body. The response may includeseveral cookie definitions by Set-Cookie HTTP header. Further to theexample, the response from the server comprises Set-Cookie value set to25. The intermediary may call upon the cookie manager 420 at step five,while passing to the cookie manager the cookie values from the response.The cookie manager 420 checks if the values received are new or updatedfor the given URL and performs any necessary updates on the incomingmap. Cookie manager 420 also checks if client consumed cookies should bereturned to intermediary for web browser consumption. At step six, theintermediary sends to the web browser of the client 102 the responsefrom the server with server consumed cookies removed from the header andclient consumed cookies added to the header.

In further details, FIG. 4A depicts a client 102 initiatingcommunication with a first request destined for the server 106 bysending the first request to the intermediary 200. Arrow 1 in FIG. 4Asignifies the transmission of the first requesthttp://abc.com/dir/index.asp to the intermediary 200. In someembodiments, the first request is transmitted by a server 106, anintermediary 200 or any other device on the network 104. The firstrequest may or may not include a cookie. In some embodiments, the firstrequest includes a URL or an HTTP request. In further embodiments, thefirst request includes a path to a resource stored on a server 106. Instill further embodiments, the first request includes a uniqueidentifier uniquely identifying client 102 out of all devicescommunicating on the network. In yet further embodiments, the firstrequest includes a unique identifier uniquely identifying a session onthe client 102. In still further embodiments, the first request includesa unique identifier uniquely identifying a user on the client 102. Insome embodiments, the client 102 transmitting the first request is notcookie configured and does not transmit cookies. In other embodiments,the client transmitting the first request is using a network or aconnection which is not secured or not desirable for transmittingsensitive information.

As illustrated by arrow 2 of the FIG. 4A, intermediary 200 receives thefirst request and forwards it to the cookie manager 420. In someembodiments, intermediary 200 initiates or invokes the cookie manager420 in response to received first request. In other embodiments,intermediary 200 initiates or invokes the cookie manager in response tothe recognition that the client 102 satisfies a set of preconditions forinvoking the cookie manager 420. The set of preconditions may includeany determination relating the client 102, the session on the client 102or the user on the client 102. Determinations may be made by theintermediary 200, client 102, server 106 or any other component ordevice on the network 104. In some embodiments, determinations are madeby policy engine 236. In some embodiments, the set of preconditionsincludes a determination that the request is from the client 102 thatdoes not support cookies. In further embodiments, the set ofpreconditions includes a determination that the client 102 uses asession or a connection that is not secured. In yet further embodiments,the set of preconditions includes a determination that the client uses anetwork that is not a secured network. In still further embodiments, theset of preconditions includes a determination that the client 102 mayaccess the requested resource or service on the server 106 requested bythe first request.

The intermediary 200 may activate or initiate the cookie manager 420 inorder to check or match the received request URL against an internal mapof cookies. The internal map of cookies may also be referred to as amap, a list or a semi-colon delimited list of cookies. In someembodiments, a policy of the policy engine 236 matches a portion of thefirst request against an internal map of cookies. The map may compriseany number of cookies, each of which may be associated, linked or pairedup with any number of clients 102, servers 106 or appliances 200. Insome embodiments, cookie manager 420 checks or matches the receivedrequest URL to a domain or a path of a message stored in the map. Insome embodiments, a policy of the policy engine 236 matches aninformation relating to the client 102 with a domain or a path of themessage stored in the map. The domain or the path of the message maymatch a URL or a portion any portion of the first request with one ormore cookies used for the client 102. In some embodiments, cookiemanager 420 or a policy detects or determines a match between a portionof the first request and one or more of cookies or a unique identifiersassociated with a client 102 or server 106. In some embodiments, cookiemanager 420 or a policy of the policy engine 236 detects or determines amatch between a portion of the first request and one or more of namevalue pairs, or value name pairs.

Cookie manager 420 may generate, provide or return one or more namevalue pairs in response to the match made between a portion of thereceived request and a cookie or one or more cookies from the internalmap of cookies. The match made between a portion of the received requestand a cookie or one or more cookies from the internal map of cookies maybe made by a policy of the policy engine 236. In some instances, cookiemanager 420 returns one or more name value pairs in response to adetermination that either a request from a client 102 or a response tothe request from the server 106 matches any one of cookies or uniqueidentifiers from the map. In some embodiments, cookie manager 420 maymatch a portion of a cookie to a portion of a URL from the receivedrequest or the response to the received request. Cookie manager 420 mayassign the matched cookie to the first request. In some embodiments,cookie manager 420 may modify the first request to include the matchedcookie. In some embodiments, cookie manager 420 generates a cookie forthe client 102 or the server 106 if a match is not made. In someembodiments, cookie manager generates a cookie for the client 102 of thefirst request and assigns the cookie to the client 102. The generatedcookie may include a value of the cookie. The value of the cookie may bea unique value uniquely associating the cookie with the client 102 inthe internal map of cookies. Cookie manager may use the value of thecookie to associate an incoming response to the first request from theserver 106 to the client 102. Cookie manager may assign the cookie tothe client 102 to be used for the first request and any other futurerequests of the client 102 to the server 106. Cookie manager 420 or anyother portion of the intermediary 200 may rewrite, modify, format, orchange the received requests such as the first request to include thematched or generated cookies or satisfy any format or contentrequirements of the requests received by the server 106.

Still referring to FIG. 4A, arrow 3 represents the step of the appliance200 transmitting the first request processed by the cookie manager 420to the server 106. The first request transmitted may be modified. Insome embodiments, the request is modified by the cookie manager 420 orthe appliance 200. The request transmitted by the intermediary 200 mayinclude one or more cookies from cookie manager 420. In someembodiments, the modified requests include the value of the cookie whichcookie manager 420 may use to associate the request to the client 102.The request which has been modified or changed by the appliance 200 orthe cookie manager 420 may be referred to as the modified request. Theserver 106 may receive the modified request in a format which isconsistent with the preferences or configurations for the requests to beprocessed by the server 106. The server 106 may receive the modifiedrequest and determine that the received modified request is a validrequest.

Arrow 4 illustrates the step of the server 106 transmitting or issuing aresponse to the modified request. The issued response may include anyinformation, service or resource the client 102 has requested. In someembodiments, the issued response includes a webpage. In otherembodiments, the issued response includes a file. In furtherembodiments, the issued response includes an application or a computersoftware program. In still further embodiments, the issued responseincludes an authentication or authorization message or a message forestablishing a session with the client 102. The response from the server106 may include the value of the cookie which may be used to uniquelyidentify the client 102 for whom the response is destined. The responsefrom the server may comprise a header and content body, either of whichmay include any of: one or more cookies, one or more cookie definitions,components or parts of one or more cookies, and values or informationrelating to or associated with the cookies. In some embodiments, thecookie definitions are set by “Set-Cookie” or “Set-Cookie2” HTTP header.“Set-Cookie” or “Set-Cookie2” HTTP header may herein be referred to asSet-Cookie.

Arrow 5 illustrates the step of the intermediary 200 communicating withcookie manager 420 and modifying the response to the first request. Inmany embodiments, the intermediary 200 transmits to the cookie manager420 one or more cookie values or unique client identifiers from theresponse from the server 106. In many embodiments, the intermediary 200transmits to the cookie manager 420 one or more cookies from theresponse from the server. The intermediary 200 may activate or initiatethe cookie manager 420 in order to check or match the URL from theresponse against the map or the list of cookies. Intermediary 200 maymodify or edit the response of the server to include a cookie that ismatched with a portion of the response. In some embodiments the cookiemanager 420 may check or match the URL, the header or any other portionof the response to a domain, a path of a message, a cookie or a part ofa cookie stored in the map. In such instances, if any cookies or uniqueidentifiers from a portion of the response are matched with a storedinformation associated with the client 102, intermediary 200 may modifyor edit the response to include the into the response the cookie of theclient 102 or any other information associated with the client 102, asdesired. In cases when the cookie manager 420 detects a match betweenthe URL from the request or the response, one or more of cookies fromthe internal map or list of cookies, one or more of name value pairs, orvalue name pairs, may be returned to the intermediary 200. In someembodiments, a policy of the policy engine 236 matches a portion of theresponse with one or more cookies or unique identifiers. Sometimes, thecookie manager 420 returns an array of name value pairs in response tothe match made between a portion of the response and a cookie or aunique identifier. In some embodiments, the cookie manager 420 may matcha portion of a cookie to a portion of a URL from the received request.In a number of embodiments, the cookie manager 420 matches a portion ofa cookie to any portion of the received request, such as a URL, a body,or a header of the request. In some embodiments, if the cookie manager420 does not match a portion of the received response to the request toany cookie, or any unique identifier, the cookie manager 420 generates anew cookie or a new unique identifier or both and assigns it/them to aclient 102 or a server 106. The cookie manager 420 may modify theresponse of the server 106 to the first request using the new generatedcookie. Such new cookies and unique identifiers for clients or serversmay be used for any future requests or responses of the same clients orservers 106. In some embodiments, cookie manager 420 determines thatthere are new or updated cookie values for the requests of the client102 or responses of the server 106 and further updates the map ordatabase accordingly. In addition, cookie manager 420 may also determineif the cookies consumed by the client 102 should be returned to theintermediary 200 for web browser consumption.

Still referring to FIG. 4A, arrow 6 illustrates a step of theintermediary 200 sending or forwarding the modified response to theclient 102 via a downstream response. In some instances, the downstreamresponse may be referred to as the transmission from the server 106, viathe intermediary 200, towards the client 102. Similarly, the upstreamcommunication may be any communication from the client 102, via theintermediary 200, and towards the server 106. In some embodiments, themodified response does not include any cookies. In further embodiments,the modified response includes the unique client identifier which isused by the cookie manager 420 to associate one or more client 102associated cookies to the client 102. In still further embodiments, themodified response includes any format desired or accepted by the client102. The modified response from the intermediary 200 to the client 102may comprise server consumed cookies removed from response. In someembodiments, the modified response forwarded may comprise clientconsumed cookies re-added to the header or any other part of theresponse. In many embodiments, the modified response from theintermediary 200 to the client 102 includes the response from the server106 modified to exclude the cookie associated with the client 102 in thecookie manager 420.

Cookie management, such as the cookie management by cookie manager 420may cause or provide services, resources or applications used by theclient 102 and provided by the server 106 to run or be provided withinthe same cookie domain namespace. The intermediary 200 may provideclient side cookie management or server side cookie management toincrease the security of the cookies transmitted between the client 102and the server 106. Cookie management, such as client side cookiemanagement, may eliminate the restrictions of the HTTP protocollimitations such as the maximum amount of cookies allowed from a singlesource per a single client. For example, in a system which may onlyallow 20 cookies per session with a client, cookie management by thecookie manager 420 of the intermediary 200 may enable the client toeliminate such limitation by reusing the cookies associated with theclient and stored in the cookie manager 420. Using client side cookiemanagement, in such examples, may enable the client 102 to continuecommunicating with the server 106 even in situations when the 20 cookiesper session limitation would affect the service provided to the client.In this case, the intermediary 200 intercepting and forwarding thecommunication between the client and the server may manage, modify,rewrite or edit portions of the requests or responses and use thecookies associated with the client or the server, thus enabling thecommunication even after more than 20 cookies are transmitted.

Clientless cookie management performed by the cookie manager 420 or theintermediary 200 may involve rewriting cookie paths on the downstreamcookie headers which are headed toward the client 102 or to the server106. In some embodiments, the cookie manager 420 or the intermediary 200forwards the responses or the requests from the client 102 or the server106 to the intended destinations without changing or modifying them. Inother embodiments, clientless cookie management performed by the cookiemanager 420 may involve state management by the intermediary 200. Thecookie manager 420 may be invoked by the intermediary for checkingupstream requests for server cookies that should be injected into thestream or communication directed to the server 106. The responses fromthe downstream communication that are intended to be modified such thatthey are stripped of the cookies may persist in the cookie manager.

Referring now to FIG. 4B, a sequence diagram of an embodiment of stepsof a method for clientless cookie management is depicted. In briefoverview, FIG. 4B illustrates a browser of the client 102 communicatingwith a web application of the server 106 via an appliance 200 and cookiemanager 420. Client 102 sends an HTTP request to the appliance 200,which herein may also be referred to as an intermediary 200.Intermediary 200 processes the request and uses cookie manager 420 tocheck for cookies. Cookie manager 420 returns the cookies associatedwith the request to the intermediary 200. The intermediary 200 modifiesthe header of the HTTP request to include the cookies and transmits themodified HTTP request to the server 106. The server 106 returns the HTTPresponse to the HTTP request. Intermediary 200 sends any cookies fromthe HTTP response to the cookie manager 420 to be added to the map usedto associate all the cookies of the client 102 with the client 102. Theintermediary 200 modifies the response to remove the cookies from theHTTP response and uses cookie manager 420 to further add any client 102related cookies to the HTTP response. The intermediary 200 transmits themodified HTTP response to the client 102.

In further overview, FIG. 4B illustrates client 102 sending a request tothe intermediary 200, herein also referred to as the proxy. The requestmay be any request to access any resource or any service provided by theserver 106. In some embodiments, the request is a HTTP request to accessa webpage or a website related service. In other embodiments, therequest is a request to establish a connection with the server 106. Infurther embodiments, the request is a request to establish a sessionwith the server 106. In still further embodiments, the request is arequest use an application provided by the server 106. In yet furtherembodiments, the request is a request to access a streaming file, suchas an audio or a video file. In yet further embodiments, the access isan access to a secure documentation. The request may include multiplerequests.

Intermediary 200 may process the received request and use cookie manager420 to check for cookies. The intermediary may process the request andestablishing which, if any, cookies client 102 includes. Processing ofthe request may further include establishing a unique client identifierto identify any further communication with the client 102. Theintermediary 200 may processes the request and forward it to the cookiemanager 420. In some embodiments, the intermediary 200 forwards aportion of the request to the cookie manager 420. In some embodiments,cookie manager 420 uses one or more maps to relate or associate client102 related information such as the unique identifiers of the clientwith cookies used for communication by the clients 102 to the server106. Similarly, the maps of the cookie manager 420 may be used toassociate any client 102 side cookies with the server 106 side cookiesthat the client 102 uses for the communication with the server 106. Insome embodiments, a unique identifier from a request is matched to aname value pair or a cookie in the map. The cookies may be associatedwith the client 102 via the map of the cookie manager 420. Cookiemanager 420 may create new cookies for the client 102 if such cookiesalready do not exist in the map of the cookie manager 420.

In some embodiments, as each request or a response is processed by theintermediary 200, the intermediary 200 checks if the URL of thetransmission being processed is server side cookie management enabled.Intermediary 200 may call the cookie manager related function such asProcessRequest( ) to do request processing. Cookie manager 420 mayfurther check an internal map, which may be a cookie manager map or acookie manager list, used to help determine if there are any incomingcookies that need to be added to the upstream request. Cookie manager420 may also record all cookies encountered for the first time in thesession inside the map for future requests. Cookie manager may alsoensure that the system is not sending certain cookies, such as appliance200 related cookies for example, to hosted web applications, such as forexample, the NSC_AAAC. In some embodiments, a function, such asProcessRequest( ) function for example, may call another function, suchas FilterCookies( ) for example, internally. In some embodiments,FilterCookies( ) may call ProcessRequest( ). In some embodiments, thetwo sets of values may be referred to as a Citrix.Fei.ClientCookies anda Citrix.Fei.ServerCookies. Cookie manager 420 may useCitrix.Fei.ClientCookies and a Citrix.Fei.ServerCookies to create asemi-colon delimited list or an internal cookie manager map, herein alsoreferred to as a cookie manager list or the map. The map may be usedduring decision making process of cookie management. The cookie manager420 may serialize the cookie manager map entries in the cookie manager420 into the two session values, Citrix.Fei.ClientCookies andCitrix.Fei.ServerCookies. The cookie manager 420 may also use these twovalues to persist to the session or associate to the session the client102 or the server 106 for any future transmissions. If the cookiemanager 420 matches the request of the client 102 to a cookie or aplurality of cookies in the map, the cookie manager 420 may transmit thecookie or the plurality of cookies to the appliance 200.

The intermediary 200 may modify the header of the HTTP request andtransmit the modified HTTP request to the server 106. In someembodiments, the cookie manager 420 modifies the request to include thecookie or the plurality of cookies that are associated with the client102. In some embodiments, the cookie manager 420 modifies a portion ofthe request, such as a URL or a heading to include a value or a set ofvalues or characters identifying a cookie. In some embodiments, cookiemanager 420 modifies the request to include or add a portion of a cookiewhich is associated with the client 102. In other embodiments, cookiemanager 420 modifies the request to include or add an unique identifierassociated with the client 102. In further embodiments, cookie manager420 modifies the request to exclude or remove a cookie or a uniqueidentifier from the request of the client. In some embodiments, anycomponent of the intermediary 200 modifies the request to include thecookie or the cookies provided by the cookie manager 420.

The intermediary 200 may perform any number of modifications to therequest. In some embodiments, intermediary 200 overwrites a portion ofthe request with one or more portions of one or more cookies. In otherembodiments, intermediary 200 adds a portion of one or more cookies, ora plurality of portions of one or more cookies to the request. In stillfurther embodiments, intermediary 200 modifies the cookie within therequest. The intermediary 200 may change one or more values orcharacters within the cookie or otherwise modify the cookie to beacceptable by the server 106. In yet further embodiments, intermediary200 encrypts a portion of the request. In still further embodiments,intermediary 200 modifies the request to accommodate any configurationrelated preferences or requirements of the server 106. The modifiedrequest may be changed such that it can be processed by the server 106.The intermediary 200 may transmit the modified request to the server106.

The server 106 may process the modified request and in responsetransmits to the intermediary 200 a response to the request. In someembodiments, the response to the request includes an HTTP transmission.In further embodiments, the response includes a webpage. In yet furtherembodiments, the response includes a file the client 102 requested. Instill further embodiments, the response includes an authenticationmessage to authenticate the client 102 on the server 106. In yet furtherembodiments, the response includes a transmission for starting oropening a session or a connection between the client 102 and server 106.In still further embodiments, the response includes an executable file,a program, a function, data, a streaming file or any other resource orservice provided by the server 106. In some embodiments, the server 106transmits to the intermediary 200 a plurality of responses to therequest.

Intermediary 200 may send any cookies from the HTTP response to thecookie manager 420 to be added to the map of the cookie manager 420. Anynew cookies added to the map of the cookie manager may be used forfuture transmissions between the client 102 and server 106. In someembodiments, the intermediary modifies the reply to exclude cookies fromthe reply. In other embodiments, the intermediary takes out the cookiesfrom the reply and transmits the cookies to the cookie manager 420. Thecookie manager 420 may compare the received cookies to the cookiesalready stored in the map. In some embodiments, cookie manager 420stores the received cookies in response to the determination that thereceived cookies were not previously stored in the map in relation tothe client 102 or the server 106. The cookies stored may be utilizedlater for the communication for the same client 102. In someembodiments, the transmission to the cookie manager 420 comprises anynumber of cookies or a portion, a cookie or a unique client identifierrelating the client 102, the server 106 or both the client 102 and theserver 106.

The intermediary 200 modifies the response to remove the cookies fromthe HTTP response. The intermediary may further use the cookie manager420 to add any client 102 related cookies to the HTTP response, if suchcookies exist or are necessary. In some embodiments, the intermediarymodifies, edits or changes the response to exclude any server 106cookies. In further embodiments, the intermediary 200 modifies theresponse to replace the server 106 cookies with client 102 cookies. Inyet further embodiments, the intermediary 200 modifies the response tosatisfy the format, configurations or preferences of the client 102, sothat the modified response may be acceptable or usable to the client102. As each response or request is processed, the intermediary 200 maydetermine if a server side cookie management or a client side cookiemanagement is enabled. In some embodiments, as server side cookiemanagement is enabled the intermediary 200 may call upon a function,such as a cookie manager 420 function ProcessResponse( ). In a number ofembodiments, as client side cookie management is enabled theintermediary 200 may call upon cookie manager 420 functionProcessResponse( ) or another function which performs cookie or uniqueidentifier management or internal cookie map management. The cookiemanager 420 may check the cookies from a received response or requestfor the server or client consumed cookies. In some embodiments, thecookie manager matches the cookies received from the request or theresponse to cookies stored or listed in the map. The cookie manager 420may also add a name value pair, registering or assigning a new cookie ora new client identifier in the map if such cookie or client identifierwas not registered, listed or assigned in the map earlier. Cookiemanager 420 may thus populate the map with new client identifier or newcookies which may be used in the future communication with the clientsand servers associated with such cookies or unique identifiers. In anumber of embodiments, cookies or Set-Cookie header may be removed fromthe response when handed back to the intermediary 200. By preventing theserver consumed cookies from being sent to the client, the system mayextend a number of cookies for a given domain to a number beyond apredetermined limit. In systems which limit the number of cookies to amaximum of 20, this feature may be useful to enable the client 102 tokeep using the service on the server 106 without reaching the limitationof 20 cookies maximum. Such practice may also prevent important cookiedata from being accessed or read in the network space beyond a firewallof the company sending out the sensitive information.

The intermediary 200 transmits the modified HTTP response to the client102. In some embodiments, the modified response includes a client 102cookie. In other embodiments, the modified response includes theoriginal request as sent by the server 106 to the intermediary 200. Instill further embodiments, the modified response includes a portion ofthe response that is reformatted to be in accordance with configurationor standards of the client 102 or the client 102 application or functionused for processing of the modified response. The intermediary 200 mayin response to the received modified response transmit to theintermediary 200 another request destined for the server 106.

The intermediary 200 may apply any of the access profiles, policies,rules and actions to any level of granularity of portions or subsets ofnetwork traffic traversing the intermediary 200. The level ofgranularity may range from fine to coarse based on the configuration.The logic, criteria or conditions of rules of access profiles, rules andpolicies described herein may be defined or specified to apply to anydesired subset or portion of network traffic or transmissionstransmitted via the appliance 200. In one aspect, the level ofgranularity refers to a degree, measurement, fineness or coarseness ofportions of network traffic to which the configuration may apply. Invery broad or coarse granularity of configuration, an access profile,rule or a policy may apply to all network traffic. In a very finegranularity configuration, an access profile or policy may apply to aspecific subset of network traffic of a particular user, such a trafficor portions of traffic of a particular application of a particular user.

In some granularity configurations, an access profile, policy or a ruleapplies to any client 102 sending a request to a server. The policy,rule or access profile may be defined to address, or apply to any client102, and may be based on any configuration of the client 102 orinformation relating the client 102, such as for example a portion theclient 102 request. Similarly, the policy, rule or access profile may bedefined to address, or apply to any server 106, and may be based on anyconfiguration of the client 106 or information relating the server 106,such as for example a portion the server 106 response. In somegranularity configurations, an access profile, policy or a rule isdefined to apply to a specific session or connection the client 102 isusing to connect to the server 106, via the appliance 200. In furtherembodiments, an access profile, policy or a rule is defined to apply toany client 102 the is connected via SSL VPN session or connection.

In further embodiments, an access profile, policy or a rule is definedto apply to any client 102 that is connected via clientless SSL VPNsession or connection. In still further embodiments, an access profile,policy or a rule is defined to apply to any client 102 that is connectedto via client based SSL VPN session or connection. In still furtherembodiments, an access profile, policy or a rule is defined to apply toany client 102 or client session that sends a request to a particularserver 106. In yet further embodiments, an access profile, policy or arule is defined to apply to any client 102 or client session thatrequests a particular application or a resource on the server. Infurther embodiments, an access profile, policy or a rule is defined toapply to any client 102 or client session based on the cookieconfiguration, for example if the cookies are enabled or disabled. Instill further embodiments, an access profile, policy or a rule isdefined to apply to any client 102 or client session that sends arequest that includes a particular URL, or a portion of a particularURL. In yet further embodiments, an access profile, policy or a rule isdefined to apply to any client 102 or client session based on a matchbetween a portion of the request sent by the client 102 and a phrase ora key of the access profile, policy or the rule. In some embodiments, anaccess profile, policy or a rule is defined to apply to any server 106or a server session based on an information relating a client 102accessing the server 106. Such information may include a portion orfeature of the request of the client 102, a setting or configuration ofthe client 102, or any other client 102 related information. In someembodiments, an access profile, policy or a rule is defined to apply toany server 106 or server session based on the configuration of theserver 106 or the features of the content that the server 106 istransmitting to the client 102.

Referring now to FIG. 4C, an embodiment of a cookie proxy data flowcontrol is illustrated. In brief overview, FIG. 4C depicts a client 102communicating with a server 106 via an intermediary 200 that manages theflow of the cookies between the client 102 and a server 106. Client 102sends a request to a server 106 via an appliance, also referred to as anintermediary 200. The request comprises a URL such as “GET /index.htmlHTTP/1.1”. Intermediary 200 intercepts the request sent by the client102 and forwards the request to the server 106. The server 106 inresponse to the request, issues a response that comprises a cookie, suchas for example, “HTTP/1.1 200 OK\nSet-Cookie: name=value”. Intermediary200 strips and stores the cookie and replaces the cookie with a clientID that uniquely identifies the client 102. The unique client ID may bea consolidated cookie and may be associated with the cookie in theintermediary 200 for future transmissions. Intermediary 200 forwards themodified response that includes the unique client ID to the client 102.The modified server's response may comprise information such as forexample, “HTTP/1.1 200 OK\nSet-cookie:NSC_AAAC=Unique client ID”. Theclient 102 transmits a second request using the unique client ID, suchas “GET/foo.html HTTP/1.1\nCookie:NSC_AAAC=Unique client ID”.Intermediary 200 receives the second request and using the unique clientID retrieves the cookie that was stored based on the unique client ID.Intermediary 200 modifies the request and inserts the previously storedcookie into the request. The modified second request may be formatted toinclude the same or a similar cookie that was used in the priortransmission, such as for example, “GET/foo.html HTTP/1.1\nSet-Cookie:name=value”. Intermediary 200 transmits the modified second request tothe server 106.

Further referring to FIG. 4C, the client 102 may initiate thecommunication with the server 106 by sending a request to theintermediary 200. In some embodiments, the request may be an HTTPrequest, such as for example, “GET /index.html HTTP/1.1”. In someembodiments, client 102 attempts to communicate with the server 106 forthe first time. In further embodiments, the client 102 transmits anyHTTP request destined for the server 106 to the intermediary 200. Theclient 102 may transmit any request to the intermediary 200 to access aresource or a service on the server 106.

The intermediary 200 may forward the request to the server 106. In someembodiments, intermediary 200 modifies the request and forwards themodified request to the server 106. In other embodiments, theintermediary 200 does not modify the request. In further embodiments,intermediary 200 forwards the request to the server 106 withoutmodifying any portion of the request. In some embodiments, intermediaryforwards the HTTP request, such as for example, “GET /index.htmlHTTP/1.1”, to the intermediary 200.

The server 106 may issue a response to the request that may include acookie. In some embodiments, the response may be, for example, “HTTP/1.1200 OK\nSet-Cookie: name value”. The cookie may be in a header of aresponse or within any other portion of the response. In someembodiments, the cookie may be included in the URL of the response. Thecookie may be any type and form of cookie and may be included anywherewithin the response.

Intermediary 200 may strip and store the cookie from the response andreplaces the cookie with a client ID that uniquely identifies the client102. Once the response of the server 106 is received by the intermediary200, the intermediary may create a cookie-jar for the given domain forthe client. The cookie jar may include or store any collection ofcookies for a given domain and client, such as client 102. In someembodiments, the cookie jar may be a file, a list, a database, an array,a data structure or a folder comprising any number of cookies or anynumber of information comprised by the cookies. In some embodiments, theintermediary 200 may strip “Set-Cookie” header from the response headerissued by the server 106 and it may store the Set-Cookie header into thecookie-jar. The intermediary 200 may also generate a unique cookie-proxysession cookie. The cookie proxy session cookie may comprise anyrelevant information the client 102 may receive from the cookie sent bythe server 106 without actually receiving the cookie. The cookie proxysession cookie may thus convey all the relevant information from thecookie sent by the server 106 to the client 102 in a manner acceptableby the client 102 or by the client 102's web browser. The intermediary200 may insert a cookie-proxy session cookie into the cookie-jar orrelate a cookie proxy session cookie with the related and correspondingcookie sent by the server 106. In a number of embodiments, theintermediary 200 may insert the cookie proxy response cookie into aresponse header of the message to be sent from the intermediary 200 tothe client 102. In some embodiments, the intermediary 200 may leave thedomain and path unchanged, while in other embodiments, the intermediarymay change either the domain or the path, or both the domain and thepath. In some embodiments, the intermediary 200 inserts a unique clientID into any part of the communication sent from the intermediary to theclient 102.

Intermediary 200 may forward the modified response to the client 102.The modified response may include a unique client identifier, such as aunique client ID. In some embodiments, the modified response includes aclient 102 cookie. In further embodiments, the modified response ismodified to be in accordance with the configuration of the client 102.In some embodiments, the modified response includes the originalresponse of the server 106 without any modifications. The modifiedserver's response may comprise information in any HTTP form, such as forexample, “HTTP/1.1 200 OK\nSet-Cookie:NSC_AAAC=Unique client ID”.

The client 102 transmits a second request using the unique client ID.The second request may be same, similar or substantially similar to thefirst request. In some embodiments, the second request includes the sameform as the first request. In further embodiments, the second request isby the same application used for transmitting the first request. In someembodiments, the second request is an HTTP request, such as“GET/foo.html HTTP/1.1\nCookie:NSC_AAAC=Unique client ID”. The secondrequest may include the unique client ID or a portion of the uniqueclient ID issued by the intermediary 200.

Intermediary 200 may modify the second request to include the cookieassociated with the server 106. Intermediary 200 may retrieve the server106 cookie using the unique client ID that was stored in associationwith the cookie of the server 106. Intermediary 200 may modify secondrequest and inserts the previously stored cookie into the secondrequest. Intermediary 200 may modify the request and insert thepreviously stored cookie into the request. In some embodiments,intermediary 200 modifies the request to include the previously storedcookie into the second request. The intermediary 200 may check if thecookie proxy session cookie is present. In case that the cookie proxysession cookie is present, the intermediary 200 searches the cookie jarbased on the cookie proxy session cookie. Intermediary 200 may use thecookie which is retrieved using the cookie proxy session cookie to findthe intended domain and path. Intermediary 200 may also insert cookie orcookies in the request code path and/or strip thecookie-proxy-session-cookie.

In some embodiments, the proxy 200 may keep a reference pointer fromserver-side PCB to the cookie jar in order to mark the response path. Infurther embodiments, the proxy 200 keeps a reference pointer fromsession information in the cookie in order to mark the response path. Insome embodiments, if the cookie jar has already been created for aspecific session involving a specific client 102 and a server 106, theintermediary 200 may not create a cookie jar during the second set ofcommunications within the same session. Instead, the intermediary 200may use the same cookie jar as used previously for the same session. Insome embodiments, the intermediary 200 may already have a reference to acookie jar created for a client 102 and a server 106. In a number ofembodiments, the reference to a cookie jar may be implemented through aprotocol control block or PCB, a controller, as well as any piece ofsoftware, a database, an array or a structure comprising any set ofvalues. In certain embodiments, if the client disables cookies, then nosubsequent requests from the client may comprise any cookie proxysession cookie. In some embodiments, if the client disables cookies,subsequent requests from the client may comprise a cookie proxy sessioncookie. In some embodiments, subsequent responses from a server 106 to aclient 102 may create a cookie jar with no further reference to theclient 102 or the server 106 the cookie jar is used for. In furtherembodiments, subsequent response from a server 106 to a client 102 maycreate a cookie jar with reference to the client 102 or the server 106the cookie jar is used for.

In a number of embodiments wherein a client 102 is communicating with aserver 106 for more than one time in a given session, the intermediary200 may not send the cookie-proxy session cookie again after the firstcommunication. The intermediary may use a unique client identificationmethod to uniquely identify a client 102 or a server 106. In someembodiments, a unique client identification method, also referred to asunique client ID, may be used to uniquely identify a client 102communicating to a server 106 or a server 106 communicating to a client102. In a number of embodiments, a unique client ID may be used touniquely identify a client 102 communicating or sending a message or arequest to a server 106 via an intermediary 200. In a plurality ofembodiments, a unique client ID may be used to uniquely identify aserver 106 communicating or sending a message or a request to a server106 via an intermediary 200. In some embodiments, the intermediary 200uses the unique client ID to detect and determine whether to proxy acommunication sent by a client 102.

In a number of embodiments, an intermediary 200 may perform cleaning upof cookies, determining unnecessary cookies or terminating unnecessarycookies. In a number of embodiments, an intermediary 200 may use areference pointer from a client 102's PCB to a cookie jar created forthe client 102. The modified second request may be formatted to includethe same or a similar cookie that was used in the prior transmission. Insome embodiments, the modified second request is an HTTP request, suchas a modified second HTTP request such as for example, “GET /foo.htmlHTTP/1.1\nSet-Cookie: name=value”.

Intermediary 200 may transmit the modified second request to the server106. In some embodiments, intermediary 200 transmits any number ofmodified requests to the server 106. The modified requests may be of anytype, form and format. Intermediary 200 may thus utilize the cookie jarto transmit back and forth any number of requests from the client 102and responses from the server 106.

Cookie Proxy may be any module controlling, managing or reformingcookies or transmission of cookies utilizing configuration settings. Insome embodiments, cookie proxy may be cookie manager 420. In a number ofembodiments, cookie proxy may be a part or a subcomponent of cookiemanager 420. In a plurality of embodiments, cookie proxy may comprise acookie manager 420. In certain embodiments, cookie proxy may be usedinterchangeably with cookie manager 420 and may comprise any and allfunctionality and means of performance of a cookie manager 420. In someembodiments, cookie manager 420 may be referred to as cookie proxy. In anumber of embodiments, cookie proxy may be independent of intermediary200 or a cookie manager 420. In certain embodiments, cookie proxy may bea software program or an application capable of working independentlyfrom the intermediary 200 or cookie manager 420 or working together withthe intermediary 200 or cookie manager 420.

Cookie proxy may comprise configuration settings based on a policy oraction of a policy. In a number of embodiments, a user or anadministrator may configure the cookie proxy to determine what cookiesto store into the cookie jar, and what cookies not store into cookiejar. In a plurality of embodiments, a user or an administrator maydecide for any specific domain, such as for example “www.foo.com”, ifthe intermediary 200 should proxy cookie1 and allow cookie2, cookie3 toflow through, as any of the cookie1, cookie2 and cookie3 may or may notbe client consumed cookies.

In some embodiments, cookie proxy configuration may utilize a commandline interface (CLI) syntax such as for example:

add/delete/set/unset/show cookieproxy action <action-name> <ALL [-EXCEPT <cookie-name>,[<cookie-name>,...]] |<cookie-name>,[<cookie-name>,...]>In addition the cookie proxy configuration may also comprise othersyntax such as:

add/delete/set/unset/show cookieproxy policy <name> <rule> <jar name>[-CookieProxyAction <action-name>] [<undefAction>]

In a number of embodiments, if no action is specified by the user or theadministrator, the default behavior by the cookie proxy may be to proxyall the cookies, or proxy none of the cookies, or proxy a fraction ofcookies as determined by a set of policies relating the cookie proxy.

A bind operation may bind, group, tie together or associate aconfiguration, such as a policy, with an entity, such as a user orresource. The act of binding may place the configuration into an activestate to be applied to the assigned entity. In some embodiments, a bindoperation may associate one entity with another entity or apply thefunctionality of a module to an entity. A bind operation may be anoperation performed by the cookie proxy, or by policy of the cookieproxy. In some embodiments, through configuration commands the cookieproxy may be bound to a virtual server 275. In a number of embodiments,the cookie proxy policy may be bound to a load balancing server, a GSLBserver or a VPN server. The policy rule utilized by the cookie proxy orby intermediary 200 may be any policy infrastructure rule language(PIRL) based. In some embodiments, the policies utilized by the cookieproxy or intermediary 200 may be evaluated during the response time, orthe time the intermediary or the cookie proxy to respond to a request orboth. In a number of embodiments, the policies utilized by the cookieproxy or intermediary 200 may be evaluated or implemented during theresponse time.

In some embodiments, the cookie proxying method may use the uniqueclient IDs assigned to each client. The unique client-id may be used bythe intermediary 200 to map a cookie-jar associated with a specificclient 102 to the client 102. In a number of embodiments, a client, alsoreferred to as client 102, may not send any unique client ID along witha transaction, also referred to as communication or a request. In anumber of embodiments, a cookie proxy session cookie may be used as adefault client-identification mechanism or a unique client ID. In someembodiments, client identification may be based on a client's internetprotocol address, fragments of request or HTTP communication, a uniquecomponents of a communication sent by the client 102 or the server 106,a unique feature relating a session, an SSL VPN session cookie or an SSLVPN session body. In a number of embodiments, client identification maybe configurable. In a plurality of embodiments, client identificationmay be implemented utilizing client 102's internet protocol address,also referred to as IP address.

Cookie jar cleanup, or cookie jar elimination may be completed pending adetermination of a variety of parameters such as the size of a cookiejar or timing relating a cookie jar, such as idle timing of the cookiejar for example. In some embodiments, cookie jar clean up method mayutilize a time-out of idle time or a memory-threshold. In a number ofembodiments, the cookie jar clean up may be implemented based onconfiguration associated with a cookie itself or a session timeout whichmay result in all the cookies belonging to the session being cleaned upfollowing a time-out. In some embodiments, cookie jar clean up methodmay determine which cookies to clean up based on the amount of timewhich has passed since a particular cookie or a cookie jar was last usedor accessed.

In some embodiments, CLI syntax may be used for jar and clientidentification, such as for example:

add/delete/set/unset/show cookieproxy jar <jar-name>-clientidentification <default | request based PIXL expression> -maxMem<Memory limit>In a number of embodiments, default may be to use a session cookieinserted by cookie proxying module into a header or in the URL ifcookies are not supported. In a plurality of embodiments, a rule ofpolicy may be used to find any unique header field, e.g. cookie for SSLVPN or a session cookie for LB load balancing.

In a number of embodiments, when a maximum memory limit is reached forany cookie jar, a session which is inactive for the longest duration oftime may need to be timed-out and the cookies belonging to that sessionmay need to be cleaned up. In a plurality of embodiments, a timestampmay be associated with each client 102, server 106, a client/domaincombination, or each client-server session, or any session in order toachieve a URL based cleanup.

Runtime aggregation of different policies or actions may be utilized bythe cookie proxy or the intermediary 200. In a number of embodiments,runtime aggregation of policies or actions may be used by theintermediary 200 or the cookie proxy in order to decrease theconfiguration overhead or simplify the configuration modification. In aplurality of embodiments, the intermediary 200 or the cookie proxy maybe configured to stop at first matched policy. In some embodiments, theadministrator or the user has to do the aggregation during configurationtime and create appropriate policy and action. In certain embodiments,the runtime behavior of cookie proxy action is ruled in part bysearching for a match in the policy or the list of polices and stoppingat the policy once the match is encountered. In some embodiments thecookie proxy may stop at a first policy defining or comprising a set ofcookies to be proxied or an information relating a set of cookies to beproxied, which may reduce the run-time aggregation.

Cookie jar infrastructure may be used for cookie repository, however insome instances, additional API may used for retrieving cookies based ondomain or path. In some embodiments, a hash based search mechanism maybe used to retrieve cookie proxy sessions. This method may be similar toan SSL VPN session hashing mechanism utilized in other Intermediary 200related applications. In a number of embodiments, a key for the hashfunction may depend on client identification mechanism or clientidentification protocol. In a plurality of embodiments, a different hashfunction for a different client identification mechanism may beutilized.

Cookie repository management may depend on performance or resources. Insome embodiments, cookie repository is managed by associating a cookiejar per client per domain. In a plurality of embodiments, the set ofcookie names comprises cookie names repeatedly stored in every cookiejar. In a number of embodiments, the set of cookie names used isdifferent from a cookie jar to a cookie jar, while in other embodimentsthe set of cookie names used between a plurality of cookie jarscomprises some of the same or similar names. In some embodiments, cookiejars are organized such that a cookie jar may be associated with aspecific client and with a specific virtual server handling thetransmission. In a number of embodiments, cookie jars are organized suchthat a cookie jar is associated with a client, a virtual server and adomain.

In some embodiments, a cookie jar may store no cookies which are namedsame as another cookie within the jar. In certain embodiments, a cookiejar may comprise cookie names having values associated with cookie namesin a method similar to the method utilized in headers, such as HTTPheaders for example.

Cookie proxy may comprise a number of functionalities. In someembodiments, a cookie proxy may utilize cookie proxying or any number ofembodiments discussed herein to determine if a browser may handle oraccept cookies or not. In a plurality of embodiments, a cookie proxy maydetermine if the request sent by a client 102 or a server 106 matchescertain criteria in order to determine if a browser from the client orthe server accepts or handles cookies. In some embodiments, if therequest sent by the client 102 or the server 106 matches the criteriafor being able to accept or handle cookies the intermediary 200 may senda redirect message to the client, such as:

http://incoming_host/incoming_url?new_param_added=secure_client_id alongwith a secure_client_id set-cookie.

In some embodiments, if the client comes back with the request URL suchas for example“http://incoming_host/incoming_url?new_param_added=secure_client_id”,the intermediary may verify if the unique client ID is associated withthe cookie value. If the intermediary detects a match, the intermediarymay strip off the parameter it had added and may process the originalrequest. In addition, the intermediary may also mark the cookie-proxysession to use “cookie-proxy session cookie”. In case where the uniqueclient ID is not matched with the cookie value, the intermediary mayutilize a different method such as body-rewriting for session tracking.In such a method the response body may be rewritten to include thesession info into each HTTP link.

In some embodiments, the cookie proxy or the intermediary 200 may alsocomprise cookie proxy cookie jars, also referred to as cookie proxysession cookie jars. Cookie proxy cookie jars may comprise any number ofcookie proxy cookies, also referred to as cookie proxy session cookies.In a number of embodiments, cookie proxy cookie jar may be organized orimplemented in a similar manner to the cookie jar, and may comprise allfunctionality of a cookie jar.

In certain embodiments, cookie-proxy cookie jars may be capable ofworking together with highly available applications and technologies,also referred to as HA technologies. In some embodiments, anintermediary comprising a set of cookies and unique client IDs maycommunicate the cookies and client IDs to other appliances on thenetwork. In a plurality of embodiments, a first intermediary 200comprising a cookie and a unique client ID associated with a client 102or a server 106 may share the information relating the cookie or theunique client ID with a second intermediary 200 or a plurality ofappliances 200. In cases where the first intermediary shares theinformation relating a cookie or a unique client ID with the secondappliance, the second intermediary may also be able to implementcommunication between the client and the server using the cookie and theunique client ID.

Cookie proxy, cookie manager 420 or the intermediary 200 may compriseany number of software applications or functions implemented in scriptor software in order to establish and manage cookies. In someembodiments the cookie proxy, cookie manager 420 or the intermediary 200may comprise a software code for managing a cookie jar such as forexample:

/* AppSecure Cookie-jar API. */ /* Create an empty cookie jar */as_cookie_jar_t *as_cookie_jar_create(as_allocator_t *allocator); /* Getvalue of a cookie, given name */ as_cookie_t*as_cookie_jar_get(as_cookie_jar_t *cookie_jar, astr_t *name); /* Add acookie to the jar. If nodup is set, and a previous cookie exists withthe same name,path,domain, then delete it before adding the new one */ns_status_t as_cookie_jar_add(as_cookie_jar_t *cookie_jar, as_cookie_t*cookie, int nodup); /* Delete cookies with same name, value, path anddomain as cookie */ ns_status_t as_cookie_jar_delete(as_cookie_jar_t*cookie_jar, as_cookie_t *cookie); /* Delete all name-value pairs givenname */ ns_status_t as_cookie_jar_delete_by_name(as_cookie_jar_t*cookie_jar, astr_t *name); /* Destroy cookie-jar */ voidas_cookie_jar_destroy(as_cookie_jar_t *cookie_jar); /* Parse an httpCookie header cookie string into multiple cookies and add  * them to thecookie jar */ ns_status_t as_cookie_jar_parse_cookie(as_cookie_jar_t*cookie_jar, const astr_t *cookie_string); /* Parse an http Set-Cookieheader string into multiple cookies and add them to the cookie jar */ns_status_t as_cookie_jar_parse_set_cookie(as_cookie_jar_t *cookie_jar,const astr_t *cookie_string); /* Stringify cookie jar to use as cookievalue in an http request */ astr_t*as_cookie_jar_to_cookie_string(as_allocator_t *allocator,as_component_t owner, as_cookie_jar_t *cookie_jar); /* Stringify cookiejar to use as the set-cookie value in the http response */ astr_t*as_cookie_jar_to_set_cookie_string(as_allocator_t *allocator,as_component_t owner, as_cookie_jar_t *cookie_jar); /* Create aniterator */ as_cookie_jar_iterator_t *as_cookie_jar_iterator_create(as_allocator_t *allocator as_component_towner_id, as_cookie_jar_t *cookie_jar); intas_cookie_jar_iterator_init(as_allocator_t *allocator, as_component_towner_id, as_cookie_jar_t *cookie_jar, as_cookie_jar_iterator_t *iter);int as_cookie_jar_iterate(as_cookie_jar_iterator_t *iter, as_cookie_t**cookie); void as_cookie_jar_iterator_destroy(as_allocator_t*allocator, as_cookie_jar_iterator_t *iter); intas_cookie_jar_size(as_cookie_jar_t* cookie_jar);as_cookie_jar_iterator_create(as_allocator_t *allocator, as_component_towner_id, as_cookie_jar_t *cookie_jar);.

The cookie manager or proxy may determine when, how and what cookies tomanager and/or store to cookie jars, and any of the operations describedabove, responsive to one or more policies of the policy engine, includeany rules, conditions or actions of such policies. Any of the policiesand the corresponding cookie operations may be based on a session. In anumber of embodiments, policy engine 236 provides policies or rulesthrough which an action regarding the cookie management is determined.In some embodiments, policy engine 236 may comprise a list of policiesor rules providing a means for the intermediary 200 or the cookiemanager 420 to determine an action concerning a cookie or a uniqueclient ID to be implemented. As such, through configuration and policy,the intermediary may provide fine granular control for cookiemanagement, including for clientless SSL VPN access.

In one example, a server may be providing access to a number of clientsaccessing different applications via the appliance 200. Two of suchapplications may be application1 and application2. Both applications mayuse ASP.NETSESSIONID which may be a server consumed cookie that is notused and not written to on the client side. In addition toASP.NETSESSIONID, application1 may further use a cookie AppClientInfowhich may be read and written to by a first client accessing or usingthe application 1, but not by a second client accessing the sameapplication.

In such embodiment, the configuration of the appliance 200 to handlesuch, or a similar situation, may be:

add patclass app1_clientconsumed_cookies bind patclassapp1_clientconsumed_cookies AppClientInfo set vpnclientlessAccessProfile app1_profile -ClientConsumedCookiesapp1_clientconsumed_cookies add vpn clientlessAccessPolicyapp1_access_pol “http.req.url.path.get(1).eq(\”app1”)” app1_profileThe URLs that are generated while accessing the web application1 andapplication2 are identified with term: /app1. The policy expressed inthe example above may evaluate to true the instances or situations whenthere is a HTTP request received whose URL path starts with “/app1/”.One example of such a HTTP request is “GET /app1/display.asp”. Thus, allthe cookies for such a request (for application1, or app1) except thecookie named AppClientInfo will be proxied.

In further example, an application 2 uses App2ClientCookie1 andApp2ClientCookie2 which may be used on the client side or by the client,but rest of other cookies used by it are not required to be present.Such a configuration might be:

add patclass app2_clientconsumed_cookies bind patclassapp2_clientconsumed_cookies App2ClientCookie1 bind patclassapp2_clientconsumed_cookies App2ClientCookie2 set vpnclientlessAccessProfile app2_profile -ClientConsumedCookiesapp2_clientconsumed_cookies add vpn clientlessAccessPolicyapp2_access_pol“http.req.hostname.set_text_mode(ignorecase).eq(\“app2\”)” app2_profileIn this configuration, application2 (referred as the App2) may be hostedon the web server whose hostname is app2 and thus all the cookies exceptApp2ClientCookie1 and App2ClientCookie2 will be proxied for application2(App2). In these and similar examples, the administrator may configurethe same cookie having name AppClientInfo to be proxied for application2but not for application1. Similarly, the administrator may configure thecookies having any name or being associated with any service orresource, or any client 102 or server 106 to be proxied or not to beproxied based on such and similar configurations for the policies.

In yet another example, a configuration may set all the cookies for allthe sites to be proxied in clientless VPN mode. Client consumed cookiesthat should not be proxied may be configured by specifying the name ofthe cookies in the patclass command or instruction. For example, if someapplication needs two cookies Cookie1 and Cookie2 to be present at theclient side, a configuration may be identified as:

add patclass app_bypass_cookies bind patclass app_bypass_cookies Cookie1bind patclass app_bypass_cookies Cookie2 set vpn clientlessAccessprofile<app_profile> -ClientConsumedCookies app_bypass_cookiesThis code for the profile may the be used later in theclientlessAccessPolicy instruction, such as:

add vpnclientlessAccessPolicy<policyName><rule><vpnclientlessAccessProfile>

The policy presented above may select the clientless access profileusing the clientless access such that all cookies except cookies havingname of Cookie1 and Cookie2 will be proxied. Therefore, given set ofcookies may not be proxied for a subset of traffic which is identifiedby the policy rule. The policy rule may be used to select a particularweb application or a particular server or a directory on a server. Usingconfigurations similar to the one presented above, different set ofcookies may be proxied for different set of users or groups of users orvpn vservers any of which may depend on which entity the configurationof the policy defines or addresses.

1. A method for managing cookies by an intermediary for a client, themethod comprising: receiving, by an intermediary, a response from aserver to a request of a client, the response comprising a URL and acookie; modifying, by the intermediary, the response by removing thecookie from the response and inserting a unique client identifier intothe URL; storing, by the intermediary, the removed cookie in associationwith the unique client identifier; and forwarding, by the intermediary,the modified response to the client.
 2. The method of claim 1,comprising matching, by a cookie manager, one or more values associatedwith the cookie comprised by the response to a cookie from a pluralityof cookies.
 3. The method of claim 2, wherein the modifying is inresponse to the matching.
 4. The method of claim 1, further comprising:receiving, by the intermediary, the request from the client, the requestcomprising a request URL; and matching, by a cookie manager, the requestURL with the removed cookie from a plurality of cookies.
 5. The methodof claim 1, further comprising: modifying, by the intermediary, therequest URL by adding the removed cookie; and forwarding, by theintermediary, the modified request URL to the server.
 6. The method ofclaim 4, wherein the plurality of cookies are associated with at leastone of a domain name or at least one path provided by the request URL.7. The method of claim 4, further comprising receiving, by theintermediary, one or more name value pairs from the cookie manager inresponse to the matching.
 8. The method of claim 1, wherein the responsecomprises a plurality of cookies and the modified response comprises aplurality of client identifiers associated with the plurality ofcookies.
 9. The method of claim 1, wherein the unique client identifieris a cookie proxy session cookie comprising a portion of the cookie. 10.The method of claim 1, further comprising: receiving, by theintermediary, the request from the client, the request comprising acookie proxy session cookie, the cookie proxy session cookie comprisinga portion of the cookie; matching, by the intermediary, the cookie proxysession cookie to the cookie; modifying, by the intermediary, therequest by removing the cookie proxy session cookie from the request andadding the cookie to the request; and forwarding, by the intermediary,the modified request to the server.
 11. An intermediary for managingcookies using a proxy on a network, the intermediary comprising: apacket engine of an intermediary receives a response from a server to arequest of a client, the response comprising a URL and a cookie; acookie proxy of the intermediary for modifying the response by removingthe cookie from the response and inserting a unique client identifierinto the URL; a cookie manager of the intermediary for storing theremoved cookie in association with the unique client identifier; and theintermediary for forwarding the modified response to the client.
 12. Theintermediary of claim 11, wherein the response further comprises one ormore values associated with the cookie, and wherein the cookie managermatches the one or more values associated with the cookie to a cookiefrom a plurality of cookies.
 13. The intermediary of claim 12, whereinthe modifying is in response to the matching.
 14. The intermediary ofclaim 11, wherein the packet engine receives the request from theclient, the request comprising a request URL and the cookie managermatches the request URL with the removed cookie from a plurality ofcookies.
 15. The intermediary of claim 11, wherein the intermediary:modifies the request URL by adding the removed cookie; and forwards themodified request URL to the server.
 16. The intermediary of claim 14,wherein the plurality of cookies are associated with at least one of adomain name or at least one path provided by the request URL.
 17. Theintermediary of claim 14, wherein the intermediary receives one or morename value pairs from the cookie manager in response to the matching.18. The intermediary of claim 11, wherein the response comprises aplurality of cookies and the modified response comprises a plurality ofclient identifiers associated with the plurality of cookies.
 19. Theintermediary of claim 11, wherein the unique client identifier is acookie proxy session cookie comprising a portion of the informationcomprised by the cookie.
 20. The intermediary of claim 11, wherein theintermediary: receives the request from the client, the requestcomprising a cookie proxy session cookie, the cookie proxy sessioncookie comprising a portion of the cookie; matches the cookie proxysession cookie to the cookie; modifies the request by removing thecookie proxy session cookie from the request and adding the cookie tothe request; and forwards the modified request to the server.